Yes. Med is hard enough to get into without the tunnel vision that comes with coveting a certain uni (this happened to me with monash, although different course). Turn your focus from the uni to the course and youll save a lot of heartache if you dont get in (sorry to be the pessimist, just being honest from experience)that one extra oppurtunity to do med obv...
And tmahendradatta had a great point. By doing sci or med sci you are studying with like minded students (many might have the same aspirations as you) and you can see what your learning can apply to what you want to do. By going to uni your still moving forward with your life (and youll be better for it) but going to school will take you back to square one (think about having to do year 12 - minus your friend, the comfort of a school you know etc. you'll end up doing worse than the first time, i promise you)