In my "opinion" you started your periods very young.. (9) is very young, I think I was 13, grew breasts at 11...
My niece is just like her Aunty............ CW..
It could be due to the age that you started and that you need birth control to assist in managing things, sad, but true, they weren't around back then 100 years ago, I went on birth control to manage severe cramps that left me rolling in the school yard in so much pain at school..
The pill helped me, so I am glad you are not stressed and December is not that far away, wheat bags are good too if you do feel cramps, microwave them for a couple of minutes and put it on your stomach ...
Keep your chin up.
Welcome to the Forum.