Most importantly you should see the specialist who can most likely give you a better answer. I understand with no insurance it seems impossible but it is your life, get a payment plan if you must, parents? grandparents? are you in college? go to the clinic at your school, but they willprobably tell you the same see a specialiat. That aside.... Since you are young they probably do not think heart attack or heart disease, since they are more common in older people. Mitral valve insufficiency or stenosis? abnormal heart beat, enlarged atrium, chest pain....maybe If you did not have the enlarged atrium I would think it was your anxiety (heart pain common). Obviously there is something else since physically there is a sign. Search for Transitory Benign Chest Wall Pain through google.com There are two good sites wrongdiagnosis.com and ivillage.com, one has a board with other people asking a similar question like yourself the other has a symptom-possible diagnosis finder. One more thing look up Metabolic Syndrome.. I am a nurse but with your age and those symptoms there is so much more to know about you before a doctor can diagnose...past illness, do you smoke, overweight, etc....That is what a specialist will figure out.