I've had people call Lu a teacup but she's around the 6lb - 6.5lb mark (I haven't weighed her in a little while). She's tiny around other dogs yes (like Labradors), but I know she's around the average weight for a Yorkie.
Though with the amount of people who keep saying miniature or teacup, even I started to doubt that she was a normal Yorkie size!
From my understanding, teacup Yorkies are Yorkies that are 4lbs or less when they are fully grown. I might need correcting there but that's what I've heard
Your little girl is adorable