Not sure what's wrong with him - maybe a urinary tract infection. He was a bit off when I came home from work, but went outside with me, and then when he came back in he just plunked himself down and wouldn't move around. Seemed better around 11pm so I thought I'd wait until morning and take him to the vet first thing... but now he's obviously in pain...
I just saw this - I'm sorry you didn't get a reply. You must have felt so helpess with your cat in pain in the middle of the night. What turned out to be the problem? I hope your baby is feeling better now.