Ecolier, a former user of TSR, would often say something among the lines of that if it's Medicine and something else, choose something else. Medicine is a hard, intense career, 5/6 years of university, plus lots of exams and training afterwards, and being a doctor is a tough job, with lots of unsociable hours, hard work and will take an emotional toll on you. It's madness. You need to be mad to pursue Medicine, and you need to be absolutely sure that there is nothing else you'd rather do.
That being said, if you want to help people, there are always other ways to do that that don't involve Medicine, so you might consider a different career that will allow you to still help people or you might consider pursuing finance, as you currently are, and kindly dedicate some of your time to volunteering!