Well, I don't know, there's also an argument to be made as to why you being so hard on yourself is a good thing. I can't see it as a bad thing, unless you're punching yourself in the face or something. If it's something you just realized for the first time is a mistake then of course you shouldn't be hard on yourself; this is also a good time to learn how it was a mistake and how to not make it again. If it's the umpteenth time you make the same mistake then maybe punching yourself in the face is a good idea (i.e. being hard on yourself).

This is how it works for me anyways. :P