Puberty problems almost 16 1/2?

Hello

I'm almost 16 1/2 now and I still have problems. I'm going through a growth spurt (I'm 178cm tall), I have armpit hair, a lot of pubic hair, but it's not spreading, and I ejaculate (whitish). But my voice isn't breaking. I sound like a child, I look like a child, and my penis is 10 cm long. And nothing has changed for almost 6 months. Friends who are 1-2 years younger than me look 15-17 and sound the same.

What should I do now? Go to the doctor, or wait? Or is there anything I can do to speed things up (tips).