Nine puppies is a large litter to feed. Is your dog eating enough? She should have been eating around 50% more food during the first week after giving birth and by now should have double her food intake (and by week three should have trebled it). This is best done by increasing the number of meals rather than increasing the quantity at each sitting. She also needs lots of water to allow her to produce the milk.

It is common for dogs to show a small degree of weight and hair loss after giving birth but if it is as severe as you say then it may be worth taking her to the vet, as she may require immediate hydration or application of electrolyte solutions. It is also worth checking her discharge which should have significantly reduced by now, should not contain any blood and should be odor free. If any of these indicators are not as they should be your dog requires immediate veterinary care.