You might be low on the mineral Iron, it
causes the feet and toes to cramp up and hurt. So, take a vitamin with iron in it a few times a week, and see if that works. If not, since it happens when you walk, could be you need new or more supportive shoes... one time I wore a pair of running shoes too long, and a shoenail worked its way up slightly into my heel, and took me a while to realize that's how come my heel was killing me!