I have never dealt with such a young puppy but I have read over and over that a person should have nutra cal on hand. You probably already know that. Here is a quote from a sticky here on YT:
2. Tube of Nutra Cal for Puppies (pet’s mart) administered in doses of 2cc each day after breakfast for at least 3 months. This is a high calorie supplement to head off hypoglycemia and give your puppy lots of energy as it grows. I've also read that you have to work hard on the socialization area when they come to you so young. Hopefully there will be some more experienced member that will post and help you. This is more like a "bump" than anything.
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Joanne
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