My beautiful son has been so calm and cooperative this easter hols, we have had a lovely time. But when he has had occasional temper outbursts they have been bigger and louder and he has been biting himself, which he used to when he was three (he's just turned 6). But just now he was out in the garden doing his own thing, when he suddenly walked straight up to his sister(completely unprovoked she wasn't even paying him any attention) and head butted her in the forehead. Not particularly hard, but enough to upset her and shock me. Of course I immediately told him off and when i did, put both his hands around my throat and squeezed! I'm so upset I know he does not understand the danger of squeezing my neck but it frightened me, he's getting to be a big lad and he's much bigger and stronger than his sister, I'm thinking what if he did it to her?? So i made him come in for a timeout, making it clear it was for using his head on his sister and for squeezing my neck. He sat on the stairs repeating whacking his head back really hard on the step and screaming, biting his hand very hard and then....started strangling himself :( has anyone else experienced this sort of behaviour? I'm so shocked, he's always self harmed as in head banged and bitten his hand, but this is new and it scares me.