Well, congratulations on your new baby..... But you have to realize she is really, really young - should probably still be with her mother, in fact!
So you have got to pay attention to her eating and drinking - which it seems like you are. Pups do sleep a lot.
Do you have a crate for her to sleep in? How about nutrical for hypoglycemia and/or stress.
Hopefully one of the very experienced breeders will come forth and give you further guidance!
Your heart is about the belong to that little pup