It is feasible actually. Graduated med school with two people in their late 30s, early 40s. You didn't ask for it but be forewarned: it'll take 10 years before you have a realistic taste of what the job actually is like. I don't usually speak in absolutes, but I will confidently claim that no amount of shadowing, training, volunteering in clinics/hospitals, or family will provide you with a shortcut to that experience. Could talk for days about this, but I have a cloud to go yell at.