I had to leave him there
The emergency vet said that his bladder wasn't very full but his symptoms of straining on his litter tray and licking his bits lots, pointed to having a very early blockage.
I had to leave a £100 cheque deposit in case I didn't come back..but you have my cat of course I'm coming back. Well, I suppose some people don't.
So we have to pick Tigs up tomorrow and take him to our own vets....fingers crossed for him