Seriously, don't bother. Both courses, medicine in particular, are extremely over-subscribed. One look at a half-interested PS and your application will be in the bin.
Also - it doesn't sound like you're entirely sure what course you want to do. Studying medicine is a massive commitment, please don't do it unless you are 100% sure that it is the course for you. If not, you'll hate the next few years of your life.