Think of it this way: Do it and if you do well, you don't have to re-sit. On the off hand you revised well but did crap anyway, then either you aren't cut out for it or you did nothing in the lesson, but at least you know you tried. Do nothing, and you are almost guaranteed to do crap, not to mention going through it again next year in re-sits. And also, revising only the day before will not have a large impact. To revise well, do it weeks, months even, in advance and often. It's horrible but it's worth it.

Try xbox.com.

Get off this site, for starters.