I, too, was diagnosed with FMS in 2000. Over time, my health worsened, with chronic low-grade fevers, severe muscle weakness and other symptoms atypical of FMS. My GP said something else was going on, but he didn't know what. He thought maybe Lupus.
In Jan/08, I was dx'd with late-stage Lyme disease, and a co-infection, babesiosis. I started treatment in Jan/08, and I am very slowly getting better. In my case, the treatment will be long, and the recovery is very slow, since I went undiagnosed for 8 years.
If your gut level hunch tells you something else is going on with your health, don't stop searching for answers. And don't let anyone tell you it's all in your head. It actually could be -- literally. Lyme disease can cause many psychological problems, as well, including depression, anxiety, and other problems such as insomnia, cognitive and memory problems.
Most importantly, there is NO accurate blood test that rules out Lyme -- the diagnosis is a CLINICAL one (i.e.- based on symptoms, patient history, symptom duration/intensity).
*Abx combo tx since Jan/08*
Lyme disease - clinical dx ’08; Babesiosis (Positive IgM/IgG) '08;
GERD '04; Essential Tremor ’03; Fibromyalgia ’01; Osteoarthritis; Depression; IBS; Interstitial Cystitis