I'll entertain the thought that every post on here is serious for the sake of being fair. If he was being serious, and he did get those grades, then he got his answer.
But, to be honest, I think your grades have to be pretty bad to "not be good enough for Cambridge". Cambridge interview roughly 80 to 90 percent of applicants, and the 15 or so percent that they reject are (I suspect) mainly overseas applicants or applicants who have done badly in a number of important exams. That doesn't apply to Medicine though. I think you need to be pretty confident in your ability to apply to Cambridge for Medicine.