Hi, may I answer your health queries right now ?  Please type your query here...good morning
Hi dear, From what you describe it does not look like a heart issue. If it was something cardiac it would be associated with symptoms that are serious.Also, as you said your ECHO and ECG were normal. I would recommend1. Get X-ray shoulder done2. If it is inconclusive and pain persists please do MRI of shoulder as there could be tendinitis (inflammation of the tendon)3. Try over the counter painkiller (Tylenol or ibuprofen)I wish you an early recovery dear. Regards.