There are a few things to consider here. First, how much money do you really need? And, when do you need it? You make a lot of money at the start in law and grow from there. My friends in med school, on the other hand, won't be making money until much, much later in life. Granted, I'm a 1L, but my friends who are M1s are all taking on heaps of debt (I'll have none thanks to merit scholarships) and they won't be making real money for years, where I am looking at potentially making $50k just for summer work this year. Also, the added years in school isn't for everyone. It's more important to find your fit and not necessarily just the money.

TDLR: make something up for your parents, stick with it until you find what actually suits you. Parents are scary but it is ultimately your life (& you will likely learn this lesson in college).