Doberman Skin Condition?

Could be any number of medical conditions. The "blisters" I would suspect are puppy acne which the breed is prone to, but in conjunction with the other symptoms it could be something else also. The dog needs to go the a veterinary dermatologist if your vet is unable to identify the problem. If you cannot afford to provide the dog with the medical care she needs return her to her breeder so she can get the care she needs and deserves.