I'm fifteen, and am a 12E - F (depending on the store) NZ size, and at sixteen I am seriously considering getting a reduction. I started wearing bras in primary school, and have not gone up a cup size in nearly a year. I've had my period since I was eleven, and feel I have had all major growth.
I have red indentations in my shoulders from my bra straps, and though I have never mentioned the back pain I have to anyone else it's still there. Is it a good idea? It's both personal and medical.