The pain could be due to uterine contractions (abnormal at this stage), or some problem related to the intestines. Please consult your gynecologist immediately – a physical exam is a must to diagnose possible cause of pain and whether or not you need admission or photolytic therapy (to stop uterine contractions).
It’s normal to feel some abdominal discomfort during pregnancy, but it can be hard to determine when it’s time to head to your health care provider to get checked out. Severe and consistent abdominal pain needs immediate attention. If pain or cramping is accompanied by bleeding, fever, changes in vaginal discharge, light-hardheadedness, urinary irritation, or nausea, then you should contact your health care provider as soon as possible.
In the first 20 weeks, abdominal pain could be a warning signal for a couple of serious conditions:

• Ectopic pregnancy is the first problem that you’ll want to rule out because it can be fatal. An ectopic pregnancy occurs when the fertilized egg implants outside of the uterus, in the fallopian tube, ovaries, abdomen or the cervix. If you have an ectopic pregnancy, you will probably feel abdominal pain before you even know your pregnant because it will usually present itself anywhere from 4-7 weeks gestation. Sometimes a pregnancy test will give you a negative result when you have an ectopic pregnancy. Symptoms of an ectopic pregnancy include: bleeding or spotting, pain in the abdomen, back, shoulders or neck, dizziness and low blood pressure. The pain might become worse during bowel movements or physical activity. If you start to experience symptoms of shock accompanied with heavy bleeding, call 911 immediately.

• Miscarriage is the loss of a pregnancy within the first 20 weeks. Signs of miscarriage are: spotting, bleeding, passing tissue or clots, pain and cramping in the lower abdomen, persistent lower back pain and the absence of pregnancy symptoms. The symptoms might be hard to recognize because they can present themselves over a period of a couple days. Severe bleeding needs medical attention immediately. Otherwise, call your health care provider if you exhibit symptoms of a miscarriage.

Throughout your pregnancy abdominal pain can often be caused by normal bodily functions:

• Small periods of cramping before or during an orgasm are normal and do not warrant medical attention.
• Gas pains are more common during pregnancy because digestion is slowed and there is more pressure on the stomach and intestines.
• Constipation pain is also common during pregnancy. The growing uterus puts pressure on the rectum and slower digestion contributes to constipation. This pressure can also cause a Bowel obstruction, which requires medical attention.

During pregnancy, some causes of abdominal pain are related to the pregnancy and may or may not require medical attention:

• Round Ligament stretching around the abdomen occurs because as the pregnancy progresses, the ligaments stretch and become thicker. Short, stabbing pains commonly occur during the second trimester in response to movement. If the pain lingers after movements, you should contact a health care professional.
• Braxton Hicks contractions are common in mid to late pregnancy and act as “preparation exercises” for the uterus before giving birth. They are typically irregular and painless before 37 weeks.
• If contractions become painful or come in closer intervals before 37 weeks, then it could be a sign of premature labor. Premature labor is often accompanied by some vaginal discharge, possibly bloody mucus. You might also experience cramping and lower back pain. Get in touch with a medical professional if you suspect premature labor; it can sometimes be stopped.

There are also serious pregnancy complications that can cause abdominal pain throughout pregnancy:

• Preeclampsia is a common condition of pregnancy that is identified by a rise in blood pressure and protein in the urine. It’s unknown what the cause is. Swollen face, hands, feet and ankles can point to preeclampsia. Severe preeclampsia can cause intense abdominal pain often accompanied by nausea, vomiting, headache, and problems with your vision. Preeclampsia requires immediate medical attention and consistent monitoring until you give birth.
• Placental Abruption is the separation of the placenta from the uterus partially or completely. Bleeding or light spotting is the most apparent symptom. It can cause abdominal tenderness, back pain, contractions or one long, hard contraction of the uterus. Placental abruption needs treatment immediately.

Pregnant or not, there are causes of abdominal pain that all require medical attention:

• Stomach viruses
• Kidney stones (more common during pregnancy)
• Food poisoning
• Gallbladder issues (more common during pregnancy)
• Appendicitis
• Hepatitis or problems of the liver
• Problems with the pancreas (more common during pregnancy)
• Urinary tract infection (more common during pregnancy)

If you experience any abdominal pain during pregnancy and don’t know what the cause is, you should contact your health care provider. Do not panic if you experience abdominal pain – often times the cause of pain during pregnancy is not serious but it’s better to take a cautious approach. A health professional will be able to help you narrow down the possible causes and give you the attention you need should the situation become serious.
Missed periods and light bleeding
Not all women experience a missed period in those early weeks after conception – this is not only be confusing, but can lead to miscalculated due dates and worry that the pregnancy may not continue.
A few women will experience what is called an ‘implantation bleed’ instead of a normal period, even though they have conceived a baby.
This is where a light bleed occurs as the growing baby burrows into the lining of their mother’s uterus, usually about 12 days after the egg has been fertilised, or ‘conceived’ in the fallopian tube.
An implantation bleed will typically occur just before, or around the time, the next period would have been due. However, it is usually not as heavy, or as long as a normal period.
Doctors or midwives will usually try and find out if a woman’s last ‘period’ was normal, to avoid calculating the baby’s due date from an implantation bleed, which would miscalculate the baby’s due date at about 3 to 4 weeks later.
Occasionally, a woman will continue to have a small, red or pinkish vaginal loss for a day or so around the time that their period would have been due, for example at around 4, 8, 12 and 16 weeks of the pregnancy.
This is more common during early pregnancy, but can persist into later pregnancy as well.
Some women will experience bright spotting (fresh bleeding), or brown spotting (bleeding that happened a day or so ago), at some stage during their pregnancy. This may appear as a heavy bleed, like a period, or like a ‘light period’ or simply as something small which is noticed when wiping herself after going to the toilet.
About 50% of women who experience bleeding during the first 12 weeks of their pregnancy will continue to experience a normal pregnancy.
Spotting after intercourse is often the result of the increased sensitivity of your cervix to any kind of minor bumping or irritation. After the first trimester; spotting is less likely to occur, and even if it does, it’s still not necessarily an ominous sign. If you feel cramps in your abdomen (the area around your stomach), don’t panic right away. Sometimes cramping is nothing more than a gentle reminder to take it easy, and at other times it might be a sign of digestive problems. Occasionally, however, cramping can be an emergency signal that says you need medical attention.
Take It Easy
The muscles and ligaments that support your uterus are being pulled and stretched in all directions during pregnancy. This can cause occasional cramping. The pain might be mild or sharp. It might be particularly noticeable when you make a quick move, get up out of a chair, cough, or sneeze. This is nothing to worry about. Some women get cramps when they exercise and put additional stress on muscles and ligaments that are already strained. If you feel cramps while exercising, listen to your body. Stop and rest. This is not the time to work through pain.
Cramps can also remind you to watch what you eat. As in your prepregnancy days, poor digestion will cause cramps. If you overeat or eat the wrong foods, you might feel stomach cramps. If you are constipated, you will feel cramps that can be very painful.
Warning
Sometimes cramps are a danger signal that shouldn’t be ignored. There are three specific medical conditions that are usually accompanied by cramping:
Miscarriage. About 20 percent of all pregnancies end in a miscarriage within the first three months of pregnancy. (Miscarriage is the delivery of a baby before it is developed enough to survive outside the womb.) Severe cramping in the first trimester (often accompanied by bleeding from the vagina) can signal trouble. If you feel constant abdominal pain (with or without bleeding), call your doctor right away.    Ectopic pregnancy. When the fertilized egg settles somewhere outside the uterus, you will get a positive pregnancy test, but as the egg begins to grow it cannot survive and will cause sharp abdominal pains and bleeding.
Preterm labor. Each year, hundreds of thousands of babies are born long before they are due. These babies announce their plans for an early entrance with a variety of signals that include cramping.
If your cramps are severe and/or persistent, call your doctor immediately.