Well i don't have exactly the same experience as you with my jaw but i do beleive my jaw problems to be caused by my anxiety. First, during the night i not only bite down on my teeth all night but i also grind my teeth quite badly. My husband once told me he could here my teeth grinding together at night. Now the more anxiety i have had during a day, the more i bite down and grind at night. My hubby has confirmed this relationship between jaw tension and anxiety for me. it has gotten bad enough that i have to wear a bite plate at night. Now if by chance i sleep without it, i wake up with my whole mouth hurting, my teeth , gums and jaw just hurt from the pressure during the night. On top of it it makes me wake up with the worse kind of headaches!
Now, i have also noticed that on days where i am more anxious or have anxiety provoking thins to do the bitting down phenomena because a daytime thing. I don't grind during the day cause the sound alerts me to doing it and i stop. But i bite down and this creates immense jaw pressure. Then the lower part of my face hurts and i get really bad headaches.
On top of it now, after years of this abuse when i eat my jaw majes the weirdest clicking noise if i eat food that is hard to chew... anyway...
All this to say i definetely think jaw tension of any kind is linked to anxiety. I so beleive that! so anyway, i do not have the same experience as you but my heart goes out to you on this. I hope you find something that helps you very soon!
Btw there was another thread by radha about jaw problems and the exercises given there are pretty good. I have been using them a bit when my jaw tension gets to bad and it has helped...
Sorry i could not be more helpful.
-Diva