Pete’s completely back to normal now, and the vet phoned to say all his tests came back clear, so it probably was a stress-induced cystitis. Silly boy. He’s eating normally (I’m keeping him on wet food with added water rather than dry food for a while to keep his bladder flushed), sleeping normally, playing normally and is generally back to being great. Plus, he likes sitting in the empty cat litter bag.
I’m so grateful to the Cat Clinic for seeing us so quickly and sorting him out so well.