boobs

at what age did your boobs stop growing ? i’m curious😂 my mum said she was an a cup until she was 19 then all of a sudden boom, boobs 😂 i know everyone’s different but i was just wondering. also my boobs seem to have shrunk, they’ve gone from a c cup to an a cup. i’ve put on weight so can’t be due to losing any. It’s so random and also kinda annoying 😂 anyone know why this could’ve happened ?