You may be sensitive to the fact that you are carrying low. Pregnancy brings on all sorts of aches and pains I have found. As your uterus grows, it feels hard and puts pressure on the things around it. Sitting down kind of squishes the abdominal cavity even tighter to begin with, so that "brick" is probably just baby and its surroundings. Try to remember to mention it at your next prenatal appointment if it still has you worried.
at 2:43 AM on Jul. 9, 2008