If the "voice" is telling you it'd help because it's something different, it's both wrong and misdirected. It is wrong because self-injury will not help. It is misdirected because maybe something different WILL help, but I'd suggest the difference be in where or how you spend your free time, or taking up a new hobby, something creative to keep your hands busy, or even just doing the crossword from a newspaper to keep your mind busy for a while.