Congratulations on your pup even though it's not a yorkie
Just to let you know, RESPONSIBLE breeders do test their breeding stock for certain defects/diseases. Many will bile acid test their sires and dams and the pups for liver problems before releasing them to their new homes. I'm not a breeder, so I can't go into all the details, but hopefully a breeder will be able to tell you more about what they do to ensure that the pups are healthy.
A responsible breeder will also be there for you no matter what. They will give at LEAST a one yr health guarantee against things like liver shunt, legg-perthes, etc. And will refund at least part or all of what you paid if these things do show up in your pup...