Cut on foot that won't heal

Okay so my feet have gotten really dried out and I have a crack right in the middle of my foot kinda on the ball where all the weigh goes. It just keeps getting worse and I'm in sooooo much pain from it. I can't even walk on it anymore. I can't afford to miss any work (I'm a psw..on my feet my whole shift)..any tips on how to reduce pain and promote healing faster?