Girls, my boobs are growing like crazy?

I'm 19 and I come from a busty family. I started developing when I was 10 and they just grew and grew and I would usually go up like two cup sizes a year on average. And my growth history went like this:

10: started developing
11: B cup
12: D cup
13: DDD cup
14: E cup
15: FF cup
16: G cup (they blew up like balloons this year for some reason XD)
17: HH cup
18 and 19: J cup

and I think I may need to go up to a K cup. It's normally not that big of a pain, but lately I would buy the next cup size up and it would be a little too big for awhile, then I grow into it, then I would outgrow it within 2 weeks! And I feel like I've gone up like 4 cup sizes this year! I heard that breasts are usually done growing around 21 so is this like the grand finale? xD what should I do?
Girls, my boobs are growing like crazy?
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