Thank you, thank you, everyone who's responded, especially Tigermoth, Scummymummy, and Inkpen.
Sorry this is quite long. If you can't be bothered to read this drivel, read the last paragraph - it's quite amusing.
I haven't really got anyone to really share my feelings with, except dh. I still feel very unsettled here - am emailing friends from back home (250 miles away), but know if I phone I will just cry. Also the new school are quite critical of the old nursery and school, which obviously is the one all his old friends go to. So that's quite tricky to negotiate too. So am feeling quite lonely, and very pleased to have mumsnet. Maybe I should pay a second subscription!
Have had a few vague chats with waiting mums about the fact that he's been getting into trouble - so far they all seem fine about it - breaks the ice anyway. (I don't think he has hurt anyone very badly, which probably helps).
We had another playground incident yesterday - though this was a two-sided dispute, and both boys were disciplined. Fortunately dh had the day off work and he picked him up, so had the interview with the teacher and chat with the Head!
The school does not have a playground problem - quite the opposite, which is why they take these things so seriously. He hasn't been to school before, so the whole playground thing is new to him, so we've been talking a lot about what he can do in the playground. Anyway, he came out with a clean slate today, so that's a step in the right direction.
At least I know his teacher better than all the other mums in the class, who've been at the school for 1 - 2 yrs already!
Head and teacher want us to arrange a meeting one day soon, to discuss ds generally. There are some other concerns about behaviour. Must admit at his last nursery, they just didn't seem interested in modifying behaviour, especially during the last term when they knew he was moving and would be somebody's else's problem! So thus far it seems a relief.
The 'disrespect' thing is an issue for us too, Tigermoth. ds told the Head he was going to buy the school and sack all the teachers, and also told the dinnerladies something similar too. He doesn't seem at all scared of the Head (I'm terrified of her), and doesn't realise that being sent to the Head 3 times in your first month at school is not usual!
Sometimes I wish he was not so bright. After the first incident, he was thrilled when the Head came to see him 4 days later, asked his teacher how he was doing, and took him to her office to give him a sticker - a Head Teacher's Award - a big sticker. He was thrilled with his sticker, and top marks for rewarding good behaviour, etc. BUT My precocious son told me that evening that no-one else in his class had such a sticker, and that to get another one he had to do something really naughty, and then be good for a few days! I'm really pleased we've got open lines of communication with the school, and we have actually passed this info on to them, so they will be awarding stickers with care. However, today the Head of Infants had given him a big special sticker too (he was on playground duty yesterday, but has otherwise not been involved). So today ds tells me that he now has two big special stickers and none of his classmates have any! AAaaarrrgghhhhhh!