| | pain
im 17 and a girl. about a year ago i started having chest pains above my breast on the left side in one specific place. the pain would come at random. if i was sitting or running. i went to my cardiologist and everything seemed fine. the pain stopped shortly after. about a year later, now. the pain in my chest has come back, exept now, it is under my breast on the left side, and to the middle. NOT RIGHT side. the pain is always there. if im laying on my back, or either side, if im running, or sitting, its always there, 24-7. the pain is unberable when i breath in. the only time it doesn't hurt is when i sleep. when i was four i had a heart surgery, and then later two more. the most recent,when i was 14 i had a pulminary valve replacement. my stomach also hurts only at the bottom at random. what should i do? what could this be?