I would suggest an x-ray of his neck. But please realize I am not a veterinarian. He may just be a little stunned and not feeling like moving right now. I just don't know and I don't want to scare you but I do feel there is a reason for concern. But that's what I would do at this point if it was my tortoise. I'm hoping a veterinarian will answer soon.Just regular vets not reptile vets. When I used to touch he's taIL he would always move it but no, not anymore. . I'M LOSING HOPE </3