While early pregnancy often involves abdominal symptoms, it is not necessarily the case that any kind of "weird feeling" indicates pregnancy. Abdominal symptoms associated with early pregnancy include constipation, bloating, morning sickness, weight gain and indigestion, points out the University of Maryland Medical Center.
WebMD explains that constipation and bloating during the first trimester of pregnancy typically occur because hormonal changes in the body cause intestinal muscle contractions to slow down. As digestion slows down, the muscle that keeps food and stomach acid inside the stomach begins to relax. According to the University of Maryland Medical Center, when this occurs, acid can easily regurgitate into the esophagus, causing heartburn and indigestion. Increased physical activity, hydration and fiber intake are all helpful for the digestive discomforts caused by early pregnancy.
According to The Huffington Post, hormonal changes are also responsible for morning sickness, which is a queasy feeling that some women compare to feeling hung over. Morning sickness is not always accompanied by vomiting and is sometimes triggered by unpleasant smells. While the bulk of pregnancy weight gain occurs during the second and third trimesters, even early in pregnancy, a woman can start to feel bloated and experience problems with clothing fitting around the abdomen.