Just to add my two cents worth Cath - I know how easy it is to beat yourself up over an incident like that - as everyone has said, we all over-react and then feel awful and full of guilt. But 2 very important points are that (a) I'm sure your boys know absolutely how much you love them and (b) if a child learns discipline at home they can go out into the world and know how to behave and their lives will be much happier and their self-esteem will grow whereas kids who are allowed to get away with things at home are never really happy because they don't recognise boundaries in society at large and therefore meet conflict in every aspect of their lives. Being a parent isn't easy but you obviously love them to pieces and that's what really matters.