Welcome and love your username and the name "Ozzy". So glad you joined YT and if you will stay around, you will no doubt learn so much about Yorkies and dogs in general as we all have. At your dog's very young age, you need to watch out for hypoglycemia and symptoms of lethargy, weakness and disorientation, it could be from very low blood sugar which young, tiny puppies are often unable to successfully maintain adequate levels of in their bloodstreams and need frequent nourishment. If your dog ever starts to act like that, rub some Nutrical or local honey or Karo Syrup on the dogs gums - coat them well to get some glucose into his little system without the mixture choking him, which it might do if you put a lot down his throat.
Here is a link to several good threads on puppy care from the YorkieTalk Library - a free feature here on YT.
Puppy Care and Puppy Info Library - YorkieTalk.com Forums - Yorkshire Terrier Community