i used to be able to lay on my stomach with my arms up and under my pillow. they one day, i felt like i had a sharp pain in my heart. it makes me feel panicked and scared, and i hate it. now im ever-weary of my heart and try to eat as healthily as possible, but i cant lay that way when i go to sleep. i also have to lie on my right side rather than my left, but what's odd is that in the morning, i can roll over and im fine, its only when i go to bed that i feel it. my mom took me to the doctor when i told her about this, and the doctor poked my chest a bunch, asked me if it hurt, and when i said yes (because he was jabbing his fingers into my breast), he said it was muscular. he told me to put muscle rub on it, and that stopped the random pains during the days (it had started happening randomly during the day, causing me to tell my mother), but i am still to this day afraid to lay down. occasionally i test it to see if the odd sensation is gone, but i still feel it. could it really just be a damaged muscle? or is it my heart? and if it is just a muscle, does this mean that the remaining pain is just in my head? Another strange symptom was that this pain would only last for the time i was lying down, but when i sat up, it went away. i slept many a night sitting up in the corner of my bed, quite upset over the mysterious symptoms. i looked them up, and web MD told me that my symptoms matched pericarditis. im no doctor, so i am unsure what to think. all i can hope is that someone else understands my situation and can help me. I know some symptoms only apply to certain people due to their weight, age, or gender, so to be clear, i was 15 when this started and it i am not 16, i am overweight, but not obese, and i am female. please help me, i dont want my fear of dying young to become a reality, but knowing would help me cope, and possibly seek help sooner. thank you so very much.