My first sign that I should seriously pursue writing as a career came in college while pursuing my Bachelor's in music. I was in my final semester and I had spent the semester penning a research paper.
Back then my outward appearance was anything but "professional" in my anti-establishment punk rock attire. So, when I handed in my research paper, a semester-long labor of love on a 16th century composer and prince, Don Carlo Gesualdo (coincidentally here on HubPages now), who happened also to be a homicidal maniac, my beloved paper was returned to me with a C- grade, and a hand-scrawled note from the professor accusing me of plagiarism! Apparently, it was "too well written" for the likes of a punker. I was able to prove I had written the paper but, nonetheless, I did not know whether to be offended by the accusation, or proud of the acknowledgement of my abilities... That experience taught me much about a great many things.
The point I am making is that when you make your decision, it comes about as a result of internal calling. Kudos to you for following that calling; pursue your passion. Note that my first bachelors degree was not in English, nor in any capacity of writing, but in music performance, classical theory and composition. I did not attend college to be a writer; the "writer" part of me was discovered externally, possibly rudely, definitely by surprise.
Today, all I do is write for a living. I am a ghost screen writer of scripts, for which my compensation is more than sufficient. Chances are you have seen one of my films, but because ours is an industry that lives and breathes through signed NDA's, some projects are contractually not permitted to ever be disclosed as having been ghost written. That's okay; money is green regardless, whether overtly or contractually covertly earned.
There are a great many schools out there and, if you have the capability to be accepted for enrollment, all will serve your needs well. Since you say you were previously in med school, I do not believe that acceptance into another school will be much of a challenge.
Do you need college? Once upon a time, no. Writers who were good were discovered. Today online access has leveled the field and given everyone access, thus exposure. Now, the world is your competition, so yes, college today is needed more than ever. Decide your college by what will be most personally rewarding to you. Keep your expenses down and your standards up, and you'll prevail.