if you know medicine is what you want to do, or even if you're not sure yet, you should start as soon as you can. because many times ppl are sure med is what they want to do with their life and then take advantages of shadowing opportunities (or volunteering, or research) and realize either that yes its definitely what they want or no, its not what they expected. its never really too early to start, bc shadowing doctors helps you build relationships and connections with ppl who will later be very important for recommendations and such. as for not having covered the basic sciences, opportunites such as shadowing will help you reinforce certain material when you get to learning it, and you can always shadow at your own pace.
