Someone has to get in, why shouldn't it be you? I have lived with several med students (about 7 of them) and they are all of mixed abilities, but at the end of the day they are all normal people. They did put a lot of effort into their studies and maintained social lives. Their advice to me was to try your best, persevere and keep calm, don't get stressed about the technicals. The pathway into medicine doesn't only just test your academic skills, it also tests your social skills, your maturity and your ability to think logically and critically. It may seem difficult now, but you have the next few years to build yourself up. Try your best and at the end of the day, there are always other pathways.
I think that this has been some good advice and it definitely made things clearer to me.
Never doubt your abilities, take the pathway that your truly want. Good luck.