I highly doubt somebody thats 12 especially acts like his balls dropped. But I don't know you so I'm not the judge of that I guess.
Testicles drop at a young age. Not neccesarily meaning you've gone through puberty I think. They contract and detract to regulate temperature because sperm cells can only be made in a certain temperature.
So once a male could produce sperm, his scrotum could do that I am pretty sure >.>