DD didnt know anyone at her school, nor the area (we had flown in from living overseas the week before) and had moved into our house only the day before.
She did until 1330 on the first day, and we were expecting her to do that until Oct.
Instead when we went to collect her on the 2nd day she kicked off, proper tantrum "I WANT TO STAY"
so we left her.......
....... and she never did half days again.
She is an only, quite 'clever', but was never that confident with strangers - took her time to get to know people. Never in my wildest dreams did I think she would fit in that quickly.
Also, I was really worried when I saw the class - 15 boys, 4 girls - but she has coped with that fine.
Yes she was tired, but not that she would admit it!
Try not to worry too much - easier said than done, I know, but I actually took 2 weeks off work thinking that she wouldnt settle and that I'd be needed, but guess what, it was a bloody waste of Leave!