Hi
After all investigation are normal too your unable to take off your mind about heart attack possibility.
Symptoms you must be experiencing like chest pain and muscle pain.. are discomforting and bothering you a lot.
Not satisfied with physician opinion...n still worry.
Can be part of underlying Anxiety disorder ...
Anxiety disorders can present with variety of symtomatology
Difficulty in breathing
Chest pain
Palpitations
Sweating
Dry mouth
Giddiness
Headache
Vomiting
Diarrhea
N lot more..
But we need to know complete history to help you deal with your problem
Next Steps
consult me....After complete psychological assessment can advise medications or therapy or both accordingly
Health Tips
I understand your worried rather than getting multiple tests done ... Getting psychiatrist opinion would clarify lot of doubts