TMS really knows how to get under the skin, doesn't it? I'm familiar with the feeling that nothing is working, the pain isn't budging. I'm also familiar with the despair and hopelessness that can come from that. I feel for you!
Since you connect the appearance of anxiety to the arrival of your health problems, I bet you would benefit from Alan Gordon's Pain Recovery Program on this site. I think it's a perfect companion to Unlearn Your Pain - the two resources fill in the gaps left by each. The important thing about Alan's program is that it places a significant focus on the *fear* of pain/discomfort/poor health and also tackles the despair and hopelessness that can come from prolonged pain that won't budge. If you haven't read through it yet, give it a try. And if you have, read it a second time, even slower - just one post every day or two, keeping each topic fresh in your mind as you go about your day. I got a lot more out of the program on my second time through, once my brain was primed to hear what it had to say.
As you do the work, remember not to think of healing as an all-or-nothing thing. Take hope from your good days and see if there are more and more good days - even if they don't come often. I made the mistake for years of thinking that every flare-up meant that I wasn't "cured" and that whatever cure I was trying had failed. That would throw me into a despair spiral and then I would try the next "cure" until it, too, failed. Now I know that healing from TMS can be a long, winding process, with flare-ups and setbacks. After all, the tension causing the pain may have been with you for your whole life, or it may have been the result of recent trauma - either way, it's not something your brain will let go of easily, since it is using the pain to try to protect you. It takes what can be a frustrating amount of patience and self-compassion to heal from TMS, as you gently peel back layer after layer of mental habits designed to keep you safe, and deal with the anxiety that comes from that vulnerability.
You may just be dealing with daily pain that doesn't ever abate, but if you do have good days as you do the TMS work, remember to give these the greater focus. Each good day - or hour, or minute - is a sign that the process is working. Our brains are wired to weigh negative experiences more heavily than positive ones, and it takes constant, conscious effort to actually draw more emotional power from the pain-free moments than the painful ones. Doing it takes skill - I really liked the book "Hardwiring Happiness" by Rick Hanson as a practical guide.
I hope you keep posting and that your journey is fruitful, if winding!