Just remember what they said on the BAM open day, dont worry about, you cant change the result now. So you should just relax, concentrate on talking to the uni and try to work out a place for you. Aslong as you dont get less than 280 points or so im sure theyd consider you. I guess it depends what subject you lose it it.
But you can change it, so panicking about it isnt going to help. Just sit down and think exactly what your going to do when you get your results, be they good or bad. Which in either case, will probably be to report the the nearest pub.