I agree that it could be the tumor growth or even a new tumor. It happened to me. it was from a neck lymph node presding on a netve that was eminating shooting pain up to my ear, and used a Fentynal patch to control it, but there are other medications down the ladder, like codeine, that can be used first. My pain eventually went away from the radiation shrinkage. Pain also interferes with the body's healing process, inflamation healing, which you don't want after surgery, and effects your QOL too. I suggest calling your doctor also, and maybe even see somone in pain management, if your facility has one, to get it under control, and speech and swallow therapist who can give you exercises. Good luck with the surgery.