Do they not offer you the chance to stay back a year and do nvq's? That's what I did. Don't worry, exams aren't the be all end all. Plenty of options out there
I don't think you're allowed to re-take anything. They've made it harder every year. Feel bad for the current Yr 7's they're gonna have it really tough. But yeah what M_P said I'd try not to worry too much about them as well there's nowt you can do about them now but you can still do alright