Thanks to everyone for the help and support it's been a great help so I have practised over the last few days and can now play with few mistakes at home but I played on the school's piano yesterday in front of a few people and it all fell apart, wrong notes, pauses getting lost reading the music etc. This was easily the worst I've ever played in public and I just managed to stumble through to the end.
A lot of it could be down to nerves, different piano? I find playing in public worse than the exam it but didn't do the confidence much good.
The difficulty is it seems like I have no control over things, I've no idea how the exam will go, it could be OK, or a complete disaster or somewhere in between. I'm not sure either why it seems to have fallen apart these last 2 or 3 weeks.
I think I'm just going to to some more practise and see what happens.
Anyhow thanks for all the help and advice very much appreciated.