What should I do with my foot injury?

Last night I was being dumb and playing outside without shoes on in the backyard. I decided to do some jumping-jacks when I landed on the outside of my foot. It bent, and I heard a loud crack and felt some strong pain. I hurt it around 8:30 P.M. last night and I can walk at a slow pace. There's no discoloration so I believe it's not sprained or broken. However, I have a mandatory softball game tonight at 5:30. There is no choice of not going. What should I do to insure myself playing comfortably and not injuring myself more? *Note: I play catcher for my fast-pitch team.