Can anyone tell me whats wrong with me?

about a year ago i went to my doctor because i had severe chest pain right where my sternum is. they did an ekg and found nothing wrong with my heart. it kept happening so they reffered me to a cardiologist in wilmington. they did another ekg, hooked me up to a 24 hour monitor, did a chest x ray, and had me to a stress test to check my heart. none of them came back abnormal. so i went back home and now every so often i get the pains. they're so bad that i cant bear to do much and i edn up bawling. i feel like something is really wrong. my friend said allergies and i called my doctor and he ruled that out.