Joey is VERY CUTE! Congratulations. I think you made the right choice. ; )

However... I have to agree... 7 weeks is incredibly young to take a puppy away from the litter, especially a toy breed. Eating solids is not the big deal. Socialization IS. He needs to be around other puppies and adult dogs, to learn how to be a dog, and to learn essential manners.

You should be safe about where you take him and who he interacts with, but socializing your puppy is much more important than being neurotic about diseases. Simply ask the other dog owner, "Is your dog vaccinated? Because my puppy hasn't finished his shots." No biggie. I would be alarmed if the owner of a 7 week old puppy DIDN'T ask me that first. It is very important that his interactions are only with well-mannered, friendly dogs, and with other puppies. Enroll him in a good puppy play class. It actually is a big deal when a puppy is taken away from their siblings & mother too early, even if the mother didn't nurse him; hence the law in many states (mine included) that prohibits the sale of puppies under 8 weeks, and that is a bare minimum age.