I'm gettinbg my results tomorrow(Yes. I'm 16 and stalk Mumsnet. What of it?) and I'm not letting myself get too worried. Can't change it now, anyway. I have a twin brother who's predicted 12 A*s though, so a lot, lot of pressure.
I completely disagree with some of what's been said here about GCSEs. GCSEs are NOT the first thing universities look at. They look at your predicted grades first and foremost. GCSEs are only a tiny part along with your personal statement, module grades, predicted grades. etc. Some universities in particular, like Durham and Cambridge do expect good GCSEs, but you're not automatically ruled out because of bad GCSEs if everything else is good. I have a friend that got into Cambridge a couple of years ago. She had only one A* at GCSE and average results besides. Her PS and AS modules were great, however. It's not the end of the world if your GCSEs aren't what you expected.
If anyone tries to invalidate what I've said because I'm only 16, I will lynch them.
I hope you'll be proud of your DSs/DDs whatever they get. It's no wonder teenagers get so stressed and pressured when some of you lot consider GCSEs so important. Obviously they're not unimportant, but they're certainly not the be all and end all.
Good luck to all your DCs! It'll be over soon!