My 6 week old cocker spaniel has light pink gums what does this mean? ?

It means she is dehydrated and needs an iv with saline solution to rehydrate her body and milk replacement to keep her that way. The reason your pup is ill is because she should not be away from her mother this early, dogs have to be AT LEAST 8 weeks old, but preferably 12 weeks. Please go to your local emergency vet to get her rehydrated. Good luck.