Thanks for your question on HCM.
I can understand your situation and question.
Since your cardiac workup is normal, no need to worry much for cardiac cause.
In my opinion your
chest pain is mostly due to musculoskeletal cause because of tight inner wear.
So follow these steps for better symptomatic relief.
1. Avoid too much tight inner wear.
2. Avoid strenuous exercise.
3. Avoid heavyweight lifting.
4. Avoid bad postures in sleep and movements causing pain.
5. Take good painkiller and
muscle relaxant.
6. Apply warm water pad on affected site.
Don't worry, you will be alright.