Hi i am Dr Ahmed Aly thanks for using healthcaremagic site , I had gone through your question and understand your concerns .. Actually it might be correct as people may have a mild heart attack , clot or even myocardial infarction that pass unnoticed while sleeping and without taking any medications .it is a bit rare but it is possible . For now you may use advil tab when needed , hot massages with topical gels , spinal straightening exercises , muscle relaxants , B12 vitamin supplementation is effective for most of cases . If your pain persists i recommend a visit to your physician for proper evaluation and management of underlying cause . Please click and consider a 5 star rating with some positive feedback if the information was helpful. Wish you good health, Any further clarifications feel free to ask.