What are all the symptoms of a pregnant cat, physical and temperment?

Please only answer if you know, and know in a lot of detail. I need to know how the cat acts, and the looks of her. My cat is almost 1 and her brother and her are not spayed/neutered... and I am afraid a little incest went on.she was in heat and then one day it just stopped. and now she isnt going near anyone and when you go to pet her she runs away. she also has a fatter belly, and i feel her nipples when i hold her

The symptoms of a pregnant cat is if a cat just lay down on the ground the whole day or if it does not run. I know because I was a part time veterinarian.

maybe just go to the nearest vet and ask

my cat is pregnant,i called a vet,right before she goes into laor,she will eat like crazy. she is looking for safe place to have babies,offer her a box,robin

While the first few answers were nice, some of the facts are not true. Without a vet telling you, it is rather hard to notice until they begin to show. If you notice your cat getting fatter from the ribcage to hind quarters, slowly pet her and try to feel her belly. As the kittens develop, you will be able to feel the difference. The "stomach will continue to expand and it will feel firm, not soft like a fat cat. As she gets further along, you will notice her popping out from under couches, dressers boxes, shelves and even your washer and dryer. This is her looking for a suitable den for the litter. If this is her first litter, you may want to set something near your bed, but a little out of the way. This will make her feel safe and you can help if need be with the delivery.As for incest, I had a cat do that and there were no major problems. I would not advise the practice and suggest getting them fixed.