Frustrated!

I've been invited to submit to a small press anthology, and they're allowing two stories (no guarantee of acceptance!).  So I have one, but then I came up with an idea for the second one.  This idea has been in my head for 3 months at least.  Pretty well plotted out, which is unusual for me.  But every time I sit down to write the story, I can't get it going.  I can't get past the opening.  

I've written character studies, motivation and theme essays.  I've re-done the opening -- I can't even count how many times (well, I *could*, since they're all in the file, I just don't want to.)  Finally this weekend I told myself to just sit and write the middle then if I was having such trouble with the opening.  Instead I found myself writing the opening over AGAIN (because it seemed to be flowing and I was sure I knew where to go with it this time).  Got to the middle and realized it was STILL not going where it needed to.  

It needs to be an action story, a sword and sorcery story and it was turning into a long dialog with not enough action.  And then I realized my magic system wasn't making sense.  Plus there's a big plot problem in the motivation for the secondary character to be in danger.  And the other thing that's happening is the story is growing, not slimming down for a short story.  This is my big problem with all my short stories, they just keep expanding and expanding and I can't contain them.  I know *way* too much about these characters and their lives for it all to be contained in one short story.  I guess the obvious answer is that I should be writing novels.  But after tackling and finishing one I still don't feel I'm ready to do it again yet.  And this anthology is *not* for a novel, it's a short story dammit.  And that's what I want to write.  Except now I'm out of time and this story looks to be not salvageable.  Especially since I have only this week in which to do it.  And I can't think myself out of my magic or plot problems.  

Grrrrrrrr!  The story *will* happen.  Just not for this anthology.  

Poo.