I do not have pain, but I do take amitriptyline (Elavil) as a sleep medicine. It is an old tricyclic AD, but in low doses it works as a muscle relaxant and thus promotes sleep. It also helps prevent migraines, though not 100%. All in all, I cannot say enough good things about the medicine, which comes without side effects.

It is possible that its muscle relaxant effect would help you. Worth a try! It costs 10$ a month without insurance.