Helppppp

I took in a stray kitten A couple weeks ago. She seemed to be very young but I think it was because of malnutrition. I believe she is around 7- 8 months. I think she may be pregnant. She has been gaining weight. At first I thought it was because she was growing. But it seems to be targeted in her belly area. Her nipples have grown a bit but they haven't been turning pink. I am worried because she is so young. I don't even know if she has went into heat yet. Which is why I'm not sure if she could have gotten pregnant. Any advice? Obviously take her to the vet, but in the mean time I was looking for extra advice.

Some cats gain in the belly first. 

Nipples pinken up on day 21 in pregnant cats. She will start to show around 5 weeks.  Otherwise you will see/feel the kittens move 2 -3 weeks before delivery

If you haven't seen a vet yet, I recommend it.  She needs to be dewormed and probably needs a flea treatment, Advantage II is safe for pregnant cats.  If she isn't that far along she could be spayed/aborted but she may be too malnourished for a spay.  No vaccinations if she is pregnant, it can cause problems for the kittens.  she should also be tested for FIV.

Make sure you feed her as much food, wet and dry, for kittens as she wants.