
All sounds normal,she isn't distressed if she is napping, it won't be long if she is feeling pressure at her back end, just need her waters to go and things will get moving, the vet told me that unlike humans who are ready to push when 10cms dilated there is no such measurement with dogs.
Alarm signs are her getting distressed, seriously pushing and getting nowhere, contractions stop and don't restart or you see a dark green discharge before any pups,
Good Luck