Hello, I Am A Teenager Involved In Sports And I

Hello, I am a teenager involved in sports and I have had something hurting in my stomach for a couple of years but the last 2 months have hurt a lot. I went to the doctor and they gave me omeperazole to see if that would help. Sometimes I feel like it does and sometimes I don't. I feel like my stomach is bloaded after taking this sometimes and every once in awhile I feel like my hip or rib is bruised from something I never hit or anything. I was wondering if anybody had an idea of what it could be?