I'd recommend changing the if condition from $me isin $1- to $istok($1-,$me,32), otherwise, the script could trigger on false positives... example: if your nick is "Mark", somebody else's nick is "Mark12345", and someone ("John") slaps Mark12345, you'll end up dodging a slap that wasn't aimed at you and subsequently punching John in the face for no reason.
You could also use regex for better matching , but I'd have to check which characters aren't allowed in nicks first.