Is my kitty pregnant?

Question
Me and my boyfriend have just recently moved in with some friends. All together we have 4 cats all except 1 are males but one male is fixed. Shortly after we moved in with our friends the 2 non fixed males started mounting her we notcied and keep her locked in our room until we can affored to spade her but the males have gotten her a couple times when she got out. Now the problem is because the males are her brothers wont it hurt the kittens and how can i tell if they got her pregnant or if we stopped them in time. I cant afford to take her to the vet but if she is pregnant i want to let her out of the room so she can be around the other cats. it would be early in and she is very young. Would she even be ready to have kittens when she's maybe 6 months old?

Answer
Ashley,

Kittens can get pregnant as early as 4 months old. There are many low cost and free spay and neuter clinic available. Call your local SPCA or a veterinarians office to find out where or Google Low Cost Spay and put in the name of your city.

You can still get her spayed if she is pregnant which probably would be best all around because if they are her brothers she is pregnant by she could deformed kittens, sick kittens, kittens that die at birth, miscarriages, etc.

Here are some links to articles on heat and pregnancy that you may find helpful:
http://cats.about.com/od/reproduction/a/pregnant_signs.htm
http://cats.about.com/cs/pregnancybirth/ht/oestrus.htm
http://www.sniksnak.com/cathealth/howto15.html

I hope this helped. If you have more questions feel free to write again.