Is there such a thing as an autistic puppy?

It use to be that day 49 was considered the optimum day to place a puppy. Most breeders wait an additional few weeks to get more socializing, both from humans and species specific, before allowing pups to go.
Give it time and remember that pups need small and frequent sessions of learning. Their brain is totally developed by day 49 but their attention span is not.

 

As a person who has raised numerous guide dogs, gotten them at the age of 6 weeks, I say your puppy should be fine, as long as you socialize and train.

How I train my pups to come is; start with name recognition. Find your pups favorite treat, say his name and treat, do this several times a day, usually it doesn't take long, when you say your dogs name he will come running to get the treat. After that start saying come after the dogs name. Once all of this is reliable with no distractions, slowly add more and more distractions.

I have yet to have a puppy not learn to come when called within a week. And I don't even use a leash on them (it helps to have a fenced yard)

The most important thing is patience! If you are upset your pup will pick up on that.