I would keep some vinegar-soaked cotton balls handy in case he does go for a finger again. Even my foodiest Mexican Black King female turns me loose when she gets a whiff of it. I've also read that vodka works but I have better uses for that than getting my snake to turn loose of a finger.
Otherwise, try washing your hands in cold water for a bit, and then applying something like lemon scent hand sanitizer to them. I don't think snakes care much for citrus.