Need Help

A couple weeks ago a beautiful female stray came around. I think she is pregnant. I took her to the vet 4 days ago and he could not tell for sure if she was pregnant. She is not big at all. Since then she has become engorged with milk. I have not seen any kittens and she is over at our house all the time. She is not inside because my husband is severely allergic. Can anybody help me figure out how to tell if she is pregnant and if so why her milk came in so early?
thanks!!!

She may already have had the kittens somewhere.  If you can get her to the vet again, he may be able to tell.  Please see if you can find the kittens, just make sure they're in a safe place.  Maybe you can allow her in a shed or get her a small house?

Are you able to get her spayed (either if she hasn't had kittens or in a few weeks after the kittens are big enough to eat on their own).

There may be a rescue nearby that can help you.  The vet may be able to help, too.