When you write yourself into a corner, getting out of it is troublesome. It is a huge problem and leads to writer's block for me (and I assume, others.) When I find myself cornered while writing, I have a few ways to get out of it, and since I'm trying to steel myself for the rest of the evening's convention, I'm going to tackle a few of them before I settle in to listen.
1. A popular solution is Chandler's Law, which WikiQuote states as: "When in doubt, have a man come through a
door with a gun in his hand." This doesn't really work though in most fiction. It works in most table top games (where you exchange gun for a setting-appropriate tool.) Essentially, though, the idea is to introduce an immediate, new element to the story that needs to be addressed. This could be as simple as shifting view points and introducing a new character. Either way, this is probably a very risky move since it ups the ante in many cases or gives you new problems to work with. I think King said this is how he broke through his problem in The Stand, by just blowing up some characters. Having something decisive like that happen really helps get your story back on task, refocus on your core theme, etc., etc. But, it also can leave you, narratively, in a worse position.
2. Which leaves you with having to look at other options. You could just cut and paste the last several pages into your scrap heap file and start from an earlier point. Try and find -why- you're stuck where you are. Is it because a character isn't acting consistently? Do you feel like you've made a mistake? Replay the scene, rewrite it. Try and see if you can find the right organic method of moving forward. Sort of like that play where the guy on the date keeps getting the bell rung on him when he gets it wrong and has to start over (which I can never remember the title of but really liked.) The only problem, though, is that this doesn't move your story forward. So, you could waste loads and loads of time fine-tuning a scene or chapter. Or, if you are over-perfectionist, a few lines of conversation could trip you up.
3. Meaning that sometimes you should just skip it and come back. You don't have to write your story start to finish (or in narrative order if you want to present it differently).Write a few brief notes of what has to happen, or just a bulleted list, move on, then come back later. Yes, sometimes, giving up and moving on is an acceptable plan.
4. Anyway, I need to get back. My page won't write itself. Which is point number four: Write it anyway. So what if it sucks? Write it. You can edit a bad page; you can't edit an empty page.
I'll be watching the convention, but don't expect any more posts on it until the end, if at all. I'm mercurial like that.