<p>One caveat about majoring in nursing then apply to med school–</p>
<p>At some colleges, nursing students take science coursework (bio, physics, chem) designated for “health profession” majors. Generally these are not accepted as med school pre-reqs. You must take science coursework intended for physical & biological science majors.</p>
<p>You will also need to have a very well reasoned answer for the question: if you want to be doctor, why did you major in nursing? Because you will be asked this at every single med school interview you might receive.</p>
<p>You can certainly apply to college as an undecided. (Actually at most colleges, you cannot declare a major before midway thru your sophomore year.) Take coursework that fulfills both your preliminary nursing and pre-med requirements during your first year while getting some shadowing experience for both nursing and medicine to see which you prefer.</p>