No you are not doing anything wrong. We often feel as though a puppy is going to go full speed when we get them home. He would be more apt to go full speed if he were 3 months old. But he is a little more mature and is taking in everything around him.
If he doesn't eat in the next day or so, you can call the vet and ask him if there is anything else that should be checked on your puppy that he didn't already do.
If you are in an area where you can walk him, take him for some short walks on his leash. This is sometimes a wonderful way to bond with a dog. It may also get his mind on other things if he is depressed. The exercise will also build an appetite. And he will just enjoy being with you, because dogs love to go for walks.
Oh yeah one other thing, when you talk to him try to pretend that nothing is wrong, be happy and cheerful (dogs pick up on our moods and often mimic them). As people we tend to talk in a sad tone when someone or a pet doesn't feel well, like "what's the matter puppy. come on...don't you want to eat." (I think you can get the tone by the phrases I wrote) They pick up on this too, and sometimes feel that something is wrong. So try to be happy! ;-)
Check in tomorrow with me and let me know how it is going.
~Christina
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Peace and happiness to you and your pet! ~ Christina
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