Am i going nuts? 23 with daily left chest pain?

Okay im 23 i weigh 280 i have high blood pressure high cholesterol. Im watching what i eat and losing weight ( starting weight was 326). For the past 8 months ive been suffering from left chest pain that ranges from sharp and stabbing to t hard pain. It comes and goes daily and it seems like my back shoulders sternum are always sore. At times i can relieve the pain by arching back my shoulders and popping my sternum. Sometimes i get a feeling of heavyness that lasts a coupe seconds. I can feel my pulse everywere in my body and sometimes in my carotid artery it feels like its skipping or i have to catch a beat or im swallowing my pulse. Ive gone to the er 12 times they even know me by a first name basis. Ive had an ekg everytime cardiac enzyme test stress test echocardiogram chest x ray chest cat scan etc, and they all come back eramarkable. Ive had mri of brain cat scan of abdomen endoscopy, the only thing my doctor founf was h pilory and moderate gastritis. What do i have? do i have anxiety disorder the only times i feel anxious is when i feel this pain. Am i going nuts? Please any suggestions as to what to do next or if anybody has experienced the same. god bless