What could be causing my gastric spasms?

I am 17 years old and I have been eating very healthy lately. I go to the gym 3-4 times a week for an hour. I've been having my period for the past week and I just received the regular flu shot this Monday (which caused some nasal running and a stuffy nose but no coughing). I cannot remember anything expired or disgusting that I ate lately that could possibly cause this incredible pain. It's a sharp pain in my upper abdomen that comes and goes every 6-10 seconds. It keeps me up at night. It's been two days, and I just brought it to my mom's attention this morning. She is a physician, so she gave me Pepto Bismol, Prevacid, and Belladonna. I have not been experiencing any diarrhea or anything... yet. Help! Why won't these spasms go away? :'(