32f, sharp left side chest pains, radiating to arm, back, shoulder blade for several days. went to er on day 3 and they did tests: 2 troponin, 2 ekg, 1 chest x-ray all normal. still having pain and shortness of breath. what could this be?

This is not characteristic of coronary artery disease but could occur with pericarditis( inflammation of the heart sac). The EKG usually shows it. Other possibilities include pinched nerve between 2 ribs with sharp pain with a deep breath,or a intervertebral disc or spur pressing on a nerve root in the lower neck or upper back. Apparently not from lung.Get reexamined by your MD.or cardiologist 1st

It is not feasible to provide a meaningful opinion without additional history, physical examination and may be some tests. It would be prudent to see a doctor, preferably to start with your primary provider for an initial assessment and to ascertain if a specialist consultation is needed. Wish you good health!