Well, I smelled pee pad No. 1, and it smelled medicine-y. Not sure if that's the same as ammonia.
He peed on a new pad, and the pee looked pretty clear this time, so like everyone said, I'm going to monitor his peeing and drinking for the next few days. I really hope it's not UTI or stones. I don't know how I would be able to tell.
Thank you everyone for your great advice. I know I can always trust to find answers here.
