I'm sorry you're having TMJ issues! So painful.
Mine was resolved through (1) physical therapy (which I hadn't known could be used on such a small body part as the jaw!) & later (2) STOPPING use of a mouth guard (worn at night) that had been made for me early on. A mouth guard is sometimes enough to fix the problem, so I'm not knocking it. I think the problem was that the PT altered my jaw's alignment just enough that the mouth guard no longer fit precisely. Once I stopped using it, the pain faded pretty quickly.
I hope you have insurance that will cover either/both of these. Given my experience, I do recommend some weeks/months of PT FIRST, & only then getting a mouth guard if needed.