I'd also like to note that you have incorrectly used on INPUT.

on INPUT is trigger by several things.
-Sending a message to a channel
-(depending on event syntax) message in query
-Command
-Control-Enter'ing something

To avoid the last two, you need to check for them.
e.g.

on *:INPUT:#: {
 if ($left($1,1) != / && !$ctrlenter) {
  commands_here
 }
}