for the past two weeks my daughter has started banging her head off things, floors walls tables anything. she it both happy and angry when she does it. she bangs her head in quick succession then it hurts, and she screams. i can't understand why she does it and the problem seems to be getting worse. like i said it doesn't seem to be a tantrum thing, but she is my first and i don't know what is normal and what is not!