My Ds age 5 does this very strange thing, he clenches his hands tight brings them up towards his chest and kinda lowers his face towards them, all his muscels go ridgid and he makes a buzzing sound when he does it. He could do this hundreds of times a day, you could be in the middle of talking to him and he will do it . It started when he was a baby with arm flapping and has progressed to this movement. It is like a involentary action and he could go for months making one sound when he does it then all of a sudden change to a new noise (this particular noise is very annoying and loud ) He doesn't do it as much in public and he has told me he's trying not to do it in school as everyone looks at him
. is it some kind of tic and will he just grow out of it ?