I have the same thing, worst part was my neck! It would hurt SO bad, I feel it was part of my anxiety.
Thank god for really sunny warm weather!! I work at a golf course, and with this weather comes LOTS of manual work. It was the best thing for me, working all my muscles pushing a fertilizer spreader around and what not has really loosened up my muscles. Also being in charge of the greenskeeping crew has really kept my mind occupied through the day. Been feeling great ever since. Also and I don't know if this is related to the "flare up" of anxiety I had or not, but since I have stopped taking everything (was taking lots of Advil or tylonol for muscle pain) I have been feeling great!! Don't even have a single drink of alcohol anymore. No caffine, nothing of that nature. Feeling alive once again!! If I do start to feel a little anxious, I will take my dog for a brisk walk, really helps!!