Oh no seacow :( poor DD and you, I hope you can somehow have a restful day after this 
Thank you for understanding, I know you get it. Does he enjoy going in? It's horrible seeing the stark differences isn't it. It was the playground before school/nursery every day that first made me see that DS has issues really. It's easy not to see it so much at home because as you say, it's just your normal. And it doesn't happen so much now for us in HE basically because most of their friends also have ASD, ADHD etc. So it's more something to bond over with the other parents, they always understand. I think yesterday was difficult as it involved so much interaction with the outside world so to speak, and that shows up the differences so much more.
And there are good things too (can I admit to an awww at your DS fondling all the shrubs - my DS is a total sensory seeker too, although I know it can be awkward/embarrassing
) - they can be completely adorable, they are funny, they are kind. Yesterday morning I was saying how cute DS is when he does his maths, the way he concentrates and then explains everything to me in that funny way he has. That stuff helps. The form being all focused on the negative is going to be quite a change from the way I normally get to view it all. But I know that's the point of it.
I haven't really processed it all I think. Although I cried with relief when DD was diagnosed (I was convinced nobody else could see it) I thought that it all being official wouldn't make much difference. But it was only a few months back and times like this make me see I've really not dealt with it yet. Which is understandable really. My own diagnosis was entirely positive but I guess it is different as a parent because it makes you worry about the future and it brings it home that they won't grow out of it all.
I hope you've got some sleep, I'm going to try and get some more myself now. Sorry everyone for waffling 