4 posts on my sub, what do i do?

What I was asking about is called a tinsel lead, it is the wire that goes from the terminal into the speaker itself. From what you have written about the dots on two of the terminals, it tells me that you indeed will have 4 tinsel leads, thus it is a dual voice coil speaker.

As far as the amp goes the terminals on the amp are there for ease of wiring connections. The two + and two - terminals are in fact one of the same. It does not matter if you only use 1 set of them.

Each post has one wire coming from it to the surface of the sub

So here is what I have done.

wired (-) terminal from amp to (-) postwith the dot

wired (+) teriminal from amp to (+) post with a dot

wired remaining (-) and (+) posts on speaker together

I did some kind of crazy crap. I will wire it exactly as it is pictured in the diagram.