the EKG stress test and echo are the normal tests, if your heart has been deemed normal by these tests this is a very goog sign.. Sounds like your pain is likely muscular/skeletal.. Generally sharp chest pain is non-cardiac related.. Cardiac chest pain is usually described as being more along the lines of pressure, like a rubberband is around your heart.. Dont worry, you have had all the basic tests, there really isnt much more they can do for you without getting invasive..The only other thing i might suggest is getting a holter monitor which is a small EKG machine you wear for 24 hours.. If you dont have chest pain while that is on, maybe get an event monitor, which you wear for 30 days.. Try taking some tylenol when the chest pain starts and see if this helps.
This is one of those situations where you need to leave no option untried, esp. since it the pain is near your heart. See if you can talk with someone regarding any neurological issues. I had a terrible pain in my left leg last year and while I thought it was a leg problem, I had vertebra issues and now I get massages every couple of months and it seems to take care of the problem. It may be something involving your nervous system. Do not ignore this problem and please keep trying. Check websites such as Mayo Clinic or NIH or other reputable institutions for information, too, and get copies of all of your tests and records so you can take them to the next medical professional you see. If you are near a medical college, see if there is some kind of resource/clinic/etc. there that may be inexpensive. Many medical practitioners are also medical school professors, so perhaps you can find someone who is willing to take some time with you there. Hang in there and keep trying.