The changes in your life could be producing some underlying anxiety, maybe?
I wonder if the muscle relaxers have been keeping you from clenching.

I don't clench, I don't think, but I do have horrible leg (hip to toes) cramps that keep me from falling asleep and also wake me up. I started taking Tylenol PM recently and it has really helped--I don't get the horrible leg cramps and I get my sleep!