Its strange but Me and My Friends we did not Develop until I was 22 I ?

Me and My friends we did not develop s until most of them were 22, I remember when I was even 12 in middle school this one Black girl in my entire cl who was from Nigeria already started to develop ,its so unfair when we used to change for jim cl I remember to are Areolas were tiny little pin drops hers were large and rounded pretty much at her age,we still could basically fitt into training bras still in Highschool but are other same piers who were about to graduate at least i could say alot of them had s finally .WHen the same Black girl went to HighSchool she not only had now But Bunns ,not only I was Flat chested but I had no posture whatsoever I had a flat Backside I have a little bit on top but i could get a Bit larger I wear still an A bra one of my friends from Highschool started taking birth control pills and hers developed so quickly i was stunned ,but i heard theres side effects and including weight gain by taking the Pill?