I strongly recommend a gap year a million times over compared to jumping into a degree. Don't be scared by the idea of it, doing a degree is so very much more work, and a lot of money these days. If you have the grades, there's nothing to stop you applying for medicine in a years time! In the mean time you can get work experience, volunteering, get a job and earn some money, go travelling somewhere awesome, and just generally get a better feel for how the world works (I know I did!)