There is really no way to tell what it might be. Could be a bite, could be a swollen gland or an abscess. It really should be checked by a Vet and I hope you can come up with the funds.
I know you don't want to hear this and I certainly don't know the circumstances as to why you have a litter of puppies. Having any animal is a time consuming and a financial responsibility. People really need to spay and neuter their pets to avoid unwanted breeding.
Aside from that, the pups are here now and your responsibility. I do hope you are able to get it to the Vet.
I know but we didn't plan for her to get pregnant(my dog ran away for a cuppel of weeks and i guess that was the time she was in heat) the puppies are inside ,today the puppys swollen neck area turned red but she still moves,eats,cries but thanks anyways
Sounds like an infection which has caused irritation and swelling due to fluid build up. If this were MY pup, I would take a needle and poke a quick hole in it, to see if it would drain. if it drains, we are golden, and just keep it drained. If it does not drain after that one good poke, you have a problem that needs to be seen by a vet. Of course, I am not a vet, so anything I have said could be wrong. :)