Is it possible my very young cat is pregnant?

I've been taking cats from a farm that are wild. I'm taking all of the kittens first, and a female I brought in seems to be pregnant! She is as big as my 6 month old cat, but since she was raised on barely anything (they are not fed there) I'm assuming she's older than she looks. I take in all the cats for deworming/checkup but I'm wondering if its even possible she's pregnant? She was around males 24/7 at the farm. I've felt "wormy" tummies before and this seems firmer, like there's maybe babies inside. Is there anything I can look for to see? She's going to the vet soon but I'd really just like to know! Kind of embarrassing to go to the vet and not even know.

If she is at least 6 mo old, yes, she could be (and probably is) pregnant. I would be more surprised if she were not.

I believe the nipples are one of the first signs of pregnancy,before even the belly starts getting bigger I think

My cat I took in turned out to be pregnant and I was told she was about 4 months old so I agree that if she is 6 months and around males, most likely she is pregnant.

Agree with the others.  As you ARE going to the vets with her, you know it is fully possible  to spay her, even if the pregnancy is fairly advanced?   Its not so pleasant, but not so unpleasant as with  human babies.

A human baby, at this stage of pregnancy, is already fully alive, and taken out, would probably survive, with just some extra help.  Not so cat babies.   Premature babies more than a two-three days usually dont make it, even if they were born alive and the owner tries to help

If the vet is a fairly skilled surgeon, it is nothing especially difficult for him.   Vets cooperating with  shelters are usually more experienced with such operations than your usual  GP practictioner.