I know one of the rules is not to promote products but I have to share because my foot pain has kept me from walking. Look up insoles by Protalus. Very helpful in aligning the body.

Try soaking your feet in very cold water for several minutes and then warm water for several minutes. Cycle between the two for about 20 minutes. After that rub some magnesium oil on them. I find cold water in particular is helpful but each person may be different. Try massaging them often, when you get up and before bed and throughout the day. You can also see a massage therapist for this. It may seem obvious but try not to stand too much or walk too much.

@footpain
I don't know if this will help but ill try. I got diagnosed with plantar fasciitis right before my dx for fm, by same dr. I had to get orthotic insoles made to take the pain from my foot. If you can't get some, check Walmart by pharmacy. Should have a foot insoles electronic stand there. Expensive but effective. Hope this can help.

I have not found a complete answer as with you there are days when I just cannot walk. I purchased some insoles that have aligned my body and have helped me when I need to walk more than usual, easing the heel, foot, knee, pelvic and lower back pain. Might try them - Protalus.