Thank you for your input.

you might never be as productive as you would have been if you had chosen a career more suited to your dispositions. [...] Be aware of comparative advantage.

I would agree with this if I was better at math and physics. I maintained grades of around 90% in high school science classes, but that's by no means an indication of genius. I liked science, and was exposed to it from an early age through my parents, so a lot of concepts weren't new to me the way they were to my peers, and I was a conscientious, hard-working student. I certainly don't think I would have been more likely than any of my Grade 12 classmates to accomplish anything revolutionary in science.

don't do things just to differentiate yourself from your parents.

Ha, you noticed one of the unstated wrong reasons why I wanted to go to nursing school. Although the fact that my father was extremely unhappy in academics (for anxiety-related reasons) is good evidence that I wouldn't have done any better going straight into academic research, so I don't consider that a wrong reason.

but you might find yourself always struggling to achieve a level of minimal functionality.

"Minimal functionality" would be an excellent description of my performance as, say, a professional athlete or an musician/composer–both of which I at some point thought of pursuing as a career. I think I can achieve a lot better than that in nursing.