Thanks for your question on Health Care Magic.
I can understand your concern.
By your history and description, possibility of
musculoskeletal pain is more.
But better to rule out heart diseases because left sided
chest pain is common in cardiac diseases.
So you should definitely consult ER (emergency room) and get done ecg and 2d echo.
If both are normal then no need to worry for heart diseases.
Your pain is mostly musculoskeletal in nature.
So avoid heavyweight lifting and strenuous exercise.
Avoid movements causing pain. Avoid bad postures in sleep.
Start painkiller and
muscle relaxant drugs.
Apply warm water pad on affected areas.
Don't worry, you will be alright.
Hope I have solved your query. Wish you good health. Thanks.