Possible for a 20year old to have heart problem

I have been having heart symptoms after having an episode at the gym with speed, i took ephedrine and my heart was beating out of my chest with a stinging feeling throughout my entire body it lasted 5min or so then I just had to calm down. That occured three months ago and i have told the doctors of this incidence and they thought it was probably a panic attack. Since then my health has been deteriorated, I have lost a ton of weight and the first symptom i experienced after the incidence at the gym was that i had sharp chest pains in the middle and left side of my chest which only lased for a second or two but were strong, then i would have heart palpitations where my heart was racing after eating, i felt uncomfortably full after eating only a little bit or i would get a feeling of my heart was going to stop if i didnt eat if that makes sense. I was still able to work out for several weeks later but whenever i worked out i had what felt like a panic attack whenever i got my heart going, so i had to stop. Then my muscles have been weak and tender almost like their about to have a charlie horse any minute. I have had every symptom imaginable from, sore throat, trouble swallowing, jaw pain, nausea, diareah, constipation, indigestion, weakness, insomnia, anxiety in the past three months. The symptoms that are bothering me now the most are there is tingling and numb feeling almost constantly on the left side of my body from undearneth my armpit radiating to my hands and feet, i have trouble breathing , I feel lightheaded and my vision is blurry. I generally dont feel right like my head and body are not on the same page at times. I have had metabolic panels for blood work, inflamation (inflammation) and blood clotting blood work come back normal and i have had an ekg and echocardiogram and 48hr holter monitor come out normal. I still feel like there is something wrong with my heart, as an athlete i can tell but i am wondering if anyone has any ideas on what heart problem i could have, because i am convinced i have something wrong and i feel as if i am at the end and feel like i might die all of the sudden. I am going to try to schedule a stress test. But if anyone has any ideas it would be greatly appreciated. Thanks.

[titan22]

This sounds really familar,I thought panic attacks at gym pain in chest shortness of breath.Blood work was done,nothing came back no stroke or damage to heart.Started to get scared and bugged Dr.He sent me for stress test ,lasted 2 min on treadmill the cardiologist shut me down and sent me for  angiagram .Results were 80%,70%,100% blockage,triple bypass scheduled.Get the stress test!!!!!