Welcome to YT! Yes 6 weeks is very early and I'm glad you are educating yourself and have a resource like YT available to you. I also recommend
Yorkshire Terriers For Dummies: Tracy Barr, Peter... And
Your Yorkshire Terrier's Life: Your Complete... I brought my baby home at a little over 7 weeks, and unlike you, at the time I did not realize that was a bad thing. I did not know about YT and was very ignorant about things like the predisposition towards hypoglycemia. I did have those 2 books and he survived
and is now a healthy, happy 4 year old.