My advice is that you should take a gap year, get work experience and find out if medicine is really what you want to do. Seriously, the minimum length of time will be 5 years of uni, 2 years of foundation training and then a minimum of 3 years for your speciality. 3 years will make you a GP. 7-9 for a surgeon.
So that is 10 years (minimum). Think about it.