Please try to relax a little and enjoy your new addition to your family.
I have had 3 Yorkies. My first one, Misty, lived to be 16 years old. My second one, Kayla, the light of my life, lived to be almost 14 years old. They were both very healthy. Now I have Abby who just turned 7 months old. So far so good. I really don't think of what "might" happen. I just gave them all of my love and enjoyed them.
You will make a great mommy to her!!