My 2 year old fdog just had 8 pups and now all the sudden she has been peeing in the house.Right after I let her out she will come back in and sneek and pee somewhere.why is she doing this

She's a new mother dog. She's probably "marking her territory". That's instinctive -- claiming their territory to warn other "dogs" away. She may be perceiving you or someone in your household as a threat to her pups.

I agree with perito, she could be marking her territory.

Best to check with a vet to make sure she doesn't have an infection from having the pups :) (uti or worse)