My cat is aggressive after heat, hissing & hiding. Is she in pain?

She's probably fine but without examining her myself I cannot be sure of that. If you are worried about her you should have her checked out by your vet. As a side note, 11 months old is very young to have had kittens already. When breeding cats it is recommended to wait until they are 18-24 months of age. If she is not a breeding queen I would suggest you have her spayed in order to avoid future aggressive behavior.

I am sorry to hear about Lucy! Many cats can have personality changes at around 2 years of age as they truly reach maturity. That compounded with the fact that she is unspayed and has had a changing life situation over the past few months could definitely be affecting her personality. I would recommend an exam by a vet and having her spayed. I would recommend a feline pheromone diffuser in the house called Feliway, and a calming supplement such as Composure or Zylkene https://m.petco.com/shop/en/petcostore/product/vetri-science-composure-feline-bite-sized-chews# as well. If her aggression continues then a veterinary behaviorist consultation would be recommended.

This is the time of year when cats start to come into heat again, and if she isn't spayed and there is an intact male nearby, she may be going into heat and trying to push away her previous litter in order to make room for a new one. If you do not wish to have more kittens, I highly recommend having Chloe (and the kittens) spayed if the male cannot be. 5 cats (plus the others you mentioned) is also a lot of cats, and the sheer number may be very stressful for her. Finding homes for the kittens, or making sure everyone has access to their own food, water, bedding, litter, etc can help decrease tension.

It's possible but unfortunately, with out being able to observe the behavior, it's impossible to say. This link may help: https://vcahospitals.com/know-your-pet/estrus-cycles-in-cats I recommend to have Cheddar examined by the veterinarian. I also recommend to have her spayed. There are many health and behavioral benefits as well it stops any potential for kittens which will contribute to pet over population: https://www.petcoach.co/article/spaying-ovariohysterectomy-the-benefits-in-cats/ I hope this helps and please feel free to post any additional questions.

It doesn't affect Samra in anyway, but her in heat behavior will be extremely annoying until her heat passes. Unfortunately cats cycle quickly in heat during certain times of the year, and this will happen over and over. I recommend having her spayed so you don't have to deal with this behavior anymore.

She’s probably coming into heat again and that’s why he’s after her. I recommend spaying her when the kittens are weaned. Once she’s no longer cycling this behavior should improve. Thanks for using Petco Pet Education Center, formerly Petcoach to help you care for your cats.

Something is probably going on with her, she is possibly ill or in pain and that may be causing her to be aggressive. i would recommend taking her to the vet for a checkup and blood test to make sure she is in good health first.