We got a rescue cat from the RSPCA last summer. She was one year old, had had one litter and was spayed. However, since Tuesday she has been acting like she’s on heat. If we let her out she has about three male cats chasing her and trying to mate with her. We have kept her in for a day or two but the male cats are sitting right outside the back door yowling at her. We spray water at then but 2 minutes later they’re back again. Our cat is also quite vocal and is trying to get out of the catflap. Has anyone else had any experience of this? Thanks.
Yes, it's not that uncommon. It means that they missed a bit when they spayed her (a bit of ovary I think), so although she can't get pregnant she will still come into heat. I'm afraid it means you will need to book her for a spay again so they can find the bit they've missed.