I have spoken to the teacher and she has been keeping a close eye on him. i really do think it is just total habit now, and playing up on me for some reason. last night he went down to his nanas with robbie as they always do on a thursday night, just for 2 hours and he did the same, started holding onto my leg and crying.
the teacher said he stops as soon as i go. its just so draining and i feel really sorry for the teacher having to put up with it too.