This could be an infection setting in from something you possibly stepped on, or it could be something else, but I do know that if there is heat in the site, it isn't going to have a positive outcome. You need to go to the doctor and have it checked out without delay. Hope this helps, get well soon, good luck.
I Have A Hard, Red Knot On The Bottom, Arch Of My Foot And It's Going Up The Inner Side Of My Foot. What Could This Be?
It would be better for you to go see your nurse to sort this out if it feels hot it sounds like something is inside don't leave it if it were infected it can spread fast