Fibromyalgia cause: allergies created by caffeine
Caffeine increases gut permeability ("leaky gut"), damages mucosal barrier.
http://www.ncbi.nlm.nih.gov/pubmed/15841908
It says coffee here, but caffeine is probably the offender.
http://www.ncbi.nlm.nih.gov/pubmed/2616384
The following person experienced a new allergy to a supplement due to caffeine. The symptoms was the brain foggines, pressure in the head (this coincides with my experience and the term "fibro-fog"):
http://forum.wholeapproach.com/topic/leaky-gut-and-coffee
I have Candida overgrowth, etc. and I'm susceptible, but this still proves it. Allergies created by caffeine induce fibromyalgia symptoms.
Before beginning to take caffeine (I was on a plant based, buckwheat, meat diet) I had basically no pain from what I remember. Maybe some occasional joint or knee pain, as usual for someone with Candida overgrowth.
I then started taking a bit of caffeine almost every day for about 4 months. I had a lot of various pain during that time. All over my body, differents parts of my head had sharp pain, etc. I had a similar diet.
This created a lot of new allergies to supplements that I had no reactions to before. I stopped taking caffeine.
The same supplements I became allergic to 1.5 year ago now create symptoms that mimic fibromyalgia.
I was experimenting this summer with all this. The pattern was that I had more pain when I took those supplements.
Last week I decided to take it to an extreme. I was basically pain free and I decided to take a lot of those supplements that I thought I became allergic to because of the caffeine.
What happened: huge pain all over my body: sharp electric shocks in joints/legs/wrists/etc., different parts of my head. Bloated, achy, upset stomach. Huge fatigue, brain fog, depression, no motivation.
This is basically exactly what you describe as "fibromyalgia".
Avoid caffeine, avoid supplements/foods (allergens) that create pain.
Unfortunately, I don't think you can cure those allergies. I still have those same allergies after 1.5 year.
My grandma has fibromyalgia and she's been drinking coffee basically everyday since she was a kid and she now takes a lot of supplements (that she may have become allergic to). I believe this is the same case.
This is anecdotal of course, but I'm quite confident here. Cheers.