How do I know if my cat is pregnant?

My female cat was in heat about a month ago...Im not sure but I think she might be pregnant. How can I tell? The middle of her body is feeling a bit rounded and hard. She is wanting attention more than ever and shes meowing a lot more. Her name is Karma and I dont think shes any breed in particular. Her coat is black with brown throughout it and gold eyes.
Jess

Hi Jess and welcome!

Please read this article about cat pregnancy:
http://www.thecatsite.com/health/preg.html
and see if you recognize any of the signs. Generally spaking, if she was in heat and had access to males outside, she is almost certainly pregnant.

You really should have her spayed - it's much healthier for her and will prevent unwanted kittens. Please read the article about spaying and neutering here:
http://www.thecatsite.com/care/spay.html

Thanx...I appreciate it...one of the things that was weird is her heat only lasted about a day and then stopped. I think she probably is pg.
Jess