Yo Liz
I dunno about fibro, but it sure sounds like the stuff I go thru. I have a systemic inflamation of the autonomic nerves (autonomic neuropathy) which is in the same general family as fibro (dysautonomia) so that makes us "cousins"
Anyway, any time I get a flare up my blood sugar goes down and I feel miserable. I'm given various steroids to control the inflamations and one of the side effects of 'roids is to make blood sugar swing up and down. So between the flare up and the meds my mood are a mess.
I get sore in all the places where I've banged up my body over the years. Any joint I've ever dislocated or sprained acts up and hurts.
What I do is do something special for myself to help me get over it, and take lots of extra meds
Mike