Pectoralis major muscle for last one year pain whose in er doctor told me it can be pectoralis musel but i don't recall strching it or any thing like?

Evidence Dominant: Lack of recalling injury common; not very relevant. Medicine full of guesswork; mds not system design engineers of your body. Suggest focus on practical: detailed experimentation of all the different motions you can put the muscle through, carefully, slowly, varying intensity, all body positions practical. See which motion is most sensitive; slowly work on that. Get personal pt/md help if needed.

May need more eval: Pec maj strain is common cause of chest pain. One year is a long time to have it though. Eval your daily activities: do you carry a heavy purse, on the effected side? Pain change as you move your arms? There are also ribcage, esophageal, shoulder and neck problems that can "radiate" pain to your chest. It can even be your gallbladder, if on the right side. I assume heart has already been eval'd.