Hi and welcome
I'm sorry but I'm not a breeder but have been reading and learning here for quite a while. It sounds like she's getting ready to whelp soon now. Please read all you can, and repost this in the Breeder Talk section. One site that is extremely good is
Dog Breeding and Canine Reproduction by Debbie Jensen. Dog Breeding and Whelping guide for dog breeders.
Good luck and please do come back and tell us how everyone is doing
!!!