Could be something as simple as pulled muscle

2 heart attacks 3 stents and never had chest pain till after 2nd. And passed all tests even in the middle of a Heart attack. Cardiologists have had no answers. I would live to hear some myself.

Find a good cardiologist and get all your testing done. I learned that the heart has so many things that can go wrong and a GP or Internist won't have the skills/knowledge to get the diagnosis you need. Best Wishes.

If it's pain, probably nerve damage. If it's discomfort, probably musculoskeletal.

How about panic attacks