If you're looking at your story and having a bit of a mare, you might want to check out these posts from the scribosphere:
Phillip Barron on the rewrite process.
DMc on What Happened, What Will Happen, and why the Why It Happened is a big mistake.
And John August has several: This and This and This amongst many others.
There was a long old post on the subject somewhere that I've been trying to find ... but I've run out of time and I've got to get on with the day job. *sigh*