I don't think i have stomach ulcer but i get severe and sharp pains in my stomach most often why is that?

Possible ulcer?: Pain is a warning sign, so your symptoms signal a problem. How serious the problem and what organ(s) is(are) involved will be determined by appropriate medical evaluation--see your doctor. In the meantime, if you're taking nsaid's (aleve, advil)--discontinue them now, since you may be describing early signs of an ulcer and these drugs may be a contributant.

Need to examine: It is not feasible to provide a meaningful opinion without additional history, physical examination and may be some tests. Stop taking drugs like aspirin. You may take over the counter antacid. Even if you do not have an ulcer (which is not settled) gastritis can cause such symptoms. If your symptoms persist more than three weeks, it would be prudent to see a doctor.