Of course it's precocious puberty. The doctor is/was a moron.
My family physician has been just that for 23 years. He has examined each of my 4 kids since birth. My daughter is perfectly comfortable with him as am I. As a matter of fact she is the one who requested that he be the ONLY Dr that she see regarding her breasts. When she began menstruating earlier this year she was very frank in her questioning while visiting him for her checkup. I mean very frank. Funny you mentioned embarassment because he was quite taken aback that she was so well informed on the subject.
And, in his defense, he is not a moron either. I credit this man with saving my own life when I was 12 years old. He is the only one who recognized that the illness that I had was something other than a psychosomatic illness ( which the other morons here said it was something I conjured up simply because I didn't want to go to school ).