my DS has done the usual pre-sleep startle and woken himself up several times, but in the last week he's been doing it when wide awake, usually on the changing mat. There's no sudden noises or changes that I'm aware of, but recently he'll startle as many as 5 times during a nappy change. Is this odd, or am I just being a paranoid first time mum?! Not helped by a HV who said they should have grown out of startling by 3 months...