I have very high arches, and my foot pain can get ridiculous. What helps me is taking Neurontin (gabapentin) when the foot (nerve) pain is at its worst. I also wear elastic bands around my arches and use very soft orthotics (both from Wal-Mart in the foot care section near the pharmacy).
I also have to have a shoe with a built-in high arch and any shoe I wear can't be heavy (or my foot cramps), yet must be soft and very supportive. It can be challenging to find the right shoes! Gel soles have worked out well.
When I stand and do the dishes, I either have a thick rug or, if that's in the laundry, a large, spongy pad on the floor. They help a lot!
It may be a good idea to go to a neurologist to have him/her check you over. I found it answered many of my questions and concerns. Several years ago when fibro first hit me, I had incredibly sensitive feet which would cramp if I looked at them (so it seemed!). Thankfully, it's gotten better, but I still get flares.
Best wishes and hope you find relief! 
P.S. I couldn't wear the elastic bands at first; my feet were too sensitive. It helped to stretch out the bands a bit first, by putting them around a bottle of lotion or whatever is handy.