Thanks for posting your query.
You should go for coronary angiography
for detail analysis of coronary arteries.
You should also go for chest x ray
for detecting any lung/ bony deformities.
Yes...you may have muscle sprain
, you should consult with physician and go for muscle relaxants.
You should also go for endoscopy
for examination of GI tract.
Get well soon,
Dr. Mayank Bhargava