I'm writing a bunch of nonsense

Have you ever had the experience that you know you need to write, but you don't know what to write about?  And frankly, you don't actually feel like writing?  I am having that at the moment.  After the interview with my character on Misha's blog, I have had a lot of great ideas for my story.  Exciting ideas.  But at the same time I feel somewhat overwhelmed by all of this.  I feel like the story I need to write is too big for me.

I decided to move away from young adult/fantasy.  I want to write something real, something that matters.  In part, that is what I am doing.  My story is largely about human trafficking.  It is something that is real, it is something that is a reality in most lives.  But right now I feel almost inadequate to write that story.  I have never been confronted with the reality of human trafficking myself and now I have the audacity to try to write a story about it.

My story is going well.  I have a main character and two supporting characters so far.  I have a very good idea of where I want the story to go.  The only thing is that I feel like I'm going too quickly, like I'm missing some part of the plot.  I shouldn't let this bother me, since I am only writing the first rough draft of this and would be able to add what is needed later.  I am a bit of a perfectionist.  That is my downfall.  It is a daily struggle to just let my story be and to not worry that I'm telling more than showing, going too quickly, missing out important parts, etc.

Even right now I feel like my writing is erratic and without purpose.  I guess this is what you would call a good rant.  And it is not even a good rantable topic.  I am just carrying on and on because I must write something.  Bugger.

I don't suppose there is anything else for it than to just write the part of my story that is stuck in my head.  The part that is keeping everything else from being written.  It would take like a paragraph to get in onto the page and to get going again.  My story is my block.  That just sucks big time.  Like I said, it feels like I'm going too quickly.  There is so much that still needs to happen before my story can really go on.  But I don't know what it is.

What do you think?  Should I just go on and write the bit that is keeping me bogged down?  Or should I write the thing that needs to be written even though I don't know what it is?