there's really no time table for this, you're expectations seem
based more on a comparison with others than an appreciation for yourself. you HAVE started puberty (and, it sounds like you're into it ): You have pubic hair, your testicles, etc are making 'stuff' (that 'slimy stuff' you refer to). And I dont know what 'balls dropping' means. As long as you have 2 in your scrotum then you're ok.
Quit comapring yourself to others, it's a no win situation, there will always be someone out there that has something you don't. But puberty is a biological event, you are guaranteed admission, it will continue, and in a short time those more advanced signs (like a deeper voice, pit hair, and the like) will happen.