I noticed last night that one of my two boys made quiet squeaking noises when he was doing the toilet. After he was done I checked what he had left behind and it was poo, but the poos looked perfectly fine like they usually do. He has been passing urine because I've been watching him, and I don't think there are any signs of blood. Because it was late last night I just left it, and waited until morning. This morning when I've been watching, I've not heard him making those noises again so far, and he's acting completely normal. He's still running around and pop corning, and playing with his brother. Am I best to just keep a close eye to see if he does it again? I don't want to ring the vet just yet, because he seems perfectly fine, and I don't want to cause him stress by taking him to the vet.
Symptoms at the very start of a UTI or cystitis are often not consistent and can take several days to get properly going and become diagnosable. See a vet as soon as you notice further and more consistent symptoms. If you are lucky, it was just a one-off.