i can't tell you for sure w/o seeing the pics, but: there are some Yorkies that grow over the standard (AKC standard is 4-7 lbs) they are
"throwbacks" since they used to be bred to be much bigger than they are now-a-days...
now as for
uploading pics: when you are replying scroll down and you'll see a button that says
"manage attachments" click on that, and a window will pop up where you can upload your pictures, when you are done uploading just close that window and post your reply, TA-DA! your pics should appear at the bottom of your reply on the forum
[the way you know they uploaded correctly is by scrolling down to the manage attachment portion of the page, and the file names should be listed]
I hope this helps and congrats on your new furbaby