DS wakes up several times in the night and screams very loud/arches his back. When we pick him up, he continues to scream and kick for "quite a while" (Probably not more than minutes). This is a completely new behaviour, he used to immediately calm down after we picked him up. He seems to young for night terrors, what could it be? He is not sick, not hungry. Could he be too warm? We are clueless.Thanks for any ideas!