Had another thought...another discovery I've made (since periods stopped) is a magnesium defiency, which controls muscle spasms....and the uterus is a muscle! I'm curious if that was my problem then. You can take mag until it gives you diarrhea...then you know you've had enough and can control the dosage for your body.
Also, I'm not a doctor, but tmj also seems like a muscle and/or connective tissue disorder...you might find an improvement with hyaluronic acid ("injuv" at vitamnshoppe.com; not always easy to find at other places)) or magnesium from anywhere. I buy my dgl licorice from gnc.com (general nutrition center).