I'm not a prospective medic, but two of my best friends are.
One got 12 A*s at GCSE, 5 As at AS. They've been rejected from Oxford, Nottingham and Manchester without interview. (Did a BMAT, didn't do particularly well, hence the Oxford rejection, god knows why for the others.)
The other got 3As at GCSE, the rest Bs and a couple of Cs, AS grades were BBCD, although they've resat to get ABC. They've had an offer from Barts, and interviews at Leeds and Liverpool (rejected from Kings without interview.)
Both have reasonable amounts of work exp.
So, don't take it too badly, it obviously varies from uni to uni, and grades aren't everything!