Need some more info: how long ago did you move, when was she last in season.
Bitches are in whelp for approximately 63 days, so if you work out how long ago she could have been mated, then you would know how long you would have to wait to find out. She could be having a phantom pregnancy, but this is more likely after a season when her body thinks she is having pups but isn't really. Has she had a phantom before? Have her seasons been normal before?
The first signs of pregnancy are usually a hardening of the nipples and they turn bright pink, and the bitch usually gets a bit more cuddly towards her owners, wanting to be with you and following you closely. If she is at the stage where her tummy is swelling, then she would not have long to go,
so it would be a good idea to just get a vet to check her.
What sort of dog did you neighbours have, this might have a bearing on whether you might need vets help, depending on the size/health of the dog, i.e if it is a big dog she may need help having the puppies, or if it is a breed that has a large head such as a bulldog or staff she may need a c-section (not cheap!).