Well, I'm in my 40s and I got my period at 10 (4th grade) and had been in a bra since 3rd. I was skinny and there weren't the hormones in the food that there are today. It's just the genetics of my family - all the girls developed early for generations - my mother and my grandmother for sure. Now mixed with my husband's family's genes, my daughter is almost 12 and still probably a year away, thank goodness. So, in our family, the age is getting later.
Maybe you don't remember it because we didn't talk about it so much!
And in terms of growth, I remember my pediatrician saying you have one year to grow past the onset of menses. I am not quite 5'1", the same height I was in 5th grade, so spot on in terms of the growth calendar. Again, everyone in my family is short - men and women, so genetics.