Marie:
Usually any over use of the muscles...legs, arms, back, and neck seem to aggravate whatever it is I have. I do not have the shaking part of it, but I have seen some people in our fibro group who do. I would exhaust all tests with an endocrinologist who is willing to take "several" tests to rule/in or out adrenal dysfunction/addison's or anything endocrine related. That way, you can move on if it isn't, and if it is, it can be treated. My pain started in the legs. It progressed to basically every muscle in my body. This has taken years. I'm still trying to find answers. Good luck. Persistance is the key word here! Dawn2