Do you know when your last tetanus shot was?

I'd drop in to an emergency room and tell them what happend, you'd be surprised at how quickly things can go from "ouchy" to "worse" to "Oh ****k!", believe me, I was a paramedic student last summer and most of our calls were small things that got worse. I saw it all. Not to be an alarmist but you have nothing to lose except your finger/arm.