Print your code backwards - reverse quine
huh?, 5 characters

!hcuO


I actually have NO idea how it works, but If you download the interpreter, and if you write !hcuO, then you get Ouch!

To run this, you need to execute the program like this:

huh.exe !hcuO


It will actually look for a file called !hcuO, but it doesn't exist, so it outputs Ouch!