about the only time I have pain in my feet is when I wear shoes my feet aren't use to and they will hurt for awhile til they adjust to them and if I walk a lot. Most of my feet problem is burning on the bottoms like you walked barefooted on concrete and scratched the bottom of your feet. My one doc says that is neuropathy.
I agree 100% with Chutz about fibro being progressive and even asked my rheumy about it and he said, "it can be". When the pain first started for me it was only in my shoulders, shoulder blades and back unless I was having a flare and now it has spread all over. Actually, with each flare it seemed to spread but when the flare was over the aching and knots stayed. Compared to the rest of my body my legs and feet feel the best for now.
I hope your feet get better and it is something as simple as wearing shoes your not use to. I have a bad habit of just wearing socks around the house and not even that in the summer but I'm one that don't believe in wearing shoes in the house.
luv and hugs
Marlee