Mens health for a 16 year old..Please!?

I'm 16 years of age. I masturbate on a daily basis. My voice still squeaks from time to time. One of my testicles is much larger than the other. The smaller one is the one that hangs lower. I am worried that I may have testicular cancer. However, there is no lump present. Could my large/descended testicle just mean that I haven't fully matured yet? Also remember, I masturbate a lot and my voice still squeaks. Thank you