Our middle kid is pregers and due any day. This is our second run @ this. It can be fun and lots of work. But I don't think that a Shepard would bred with her, to much difference in size, but depending on how long she was out and who else she might have hooked up to who knows - the vet can do xrays between 45 and 55 days to let you know about pup size and how many.
Good luck
