Christina Aguilera the beverly hills hotel dog flats hat sunglasses

Yesterday afternoon we spotted a barefaced Christina Aguilera and her dog returning to the Beverly Hills Hotel, and we're not sure where she spent the night, but we're guessing it wasn't in her own bed!

We snapped the newly single singer at Premiere nightclub on Halloween, and she definitely looked like she was having a good time. So here's our question ... where DID Xtina wind up on Sunday evening?!