Sounds like its time to take the pup to the vet. Plan ahead with the front desk so you won't have to wait long, to minimize the time away from the mom.

If the vet says the pup is blind, but is otherwise fairly healthy, don't dispare. Handicapped pets can have full, wonderful lives with the right caretaker. I have a blind-from-birth cat and he's terrific I hope things go ok for you and all the pups!