Well, your appendix may be inflamed resulting in appendicitis. For that you must check with your doctor. You may also have a ruptured splee, which can cause damage there.
Probably not, although the sharp pain is troubling. Depending on the frequency of your bowel movements, it could be constipation or impaction of feces. See a doctor right away if this does not clear up within 3 days.
possible reasons for pain in the abdomen are: Pneumonia, Lung infection, Periocarditis, Broken Rib, Dislocated Rib, Collapsed Lung, Pulled Muscles, many times a muscle can be pulled without exercise
