Stories don't really follow directions very well in my experience. They jump in lines, shove other ideas out of the way. They barge right up to and demand to have an audience. Sometimes this works, the story says its piece and I can't shake the idea behind it until I've written it all down. Other times, when I set about trying to capture whatever manic energy attracted me to them in the first place I find a big emptiness.
My current story is definitely a budger. I wanted to spend some more time developing the world of the story, the back ground. But I barely set down the characters when the voice started to pop into my head. So now I'm nearly 2500 words and just trying to keep up.
It's funny how things go.