Is it as difficult to get into medical school if you already have a career in the health field?

Although I'm in highschool right now,it's been my life's goal to become a physician. I'm currently a Certified Nursing Assistant (CNA), and not to toot my own horn,but I'm pretty skilled at it,at least that's what my peers all tell me. So let's fastforward and pretend I get an above average GPA throughout unergrad school (lets say like a 3.0),and I do about average on the MCAT, but I show my CNA Certificate and my awards I've earned through highschool for doing it, do my chances sginificantly improve? Any help here for this idea,thanks!