Hugs babe!
My mum has a bad foot to and the doctor told her to put a canof peas in the freezer and when its cold get it out and roll her foot back and fwds on it - her foot is sore all over but mainly underneath.

I would suggest a podiastrist would be better - they can massage and work on the muscles - or a physio would be good as well.
A GP will most prob send you for scans and things and just suggest drugs IMO.

Hope it gets better soon!!

Kate xox