I started programming in my (very) early teens, and by the time I hit 18 I had enough skills to land a full-time programming gig. One internship before college and, in my best year, a (admittedly very) lower-middle-class income's worth of freelance work in-between homework assignments (though high 4 figures was more typical).

I loved programming and still do, but I went to college because I knew -- by the time I was 18 -- that I really wanted to do something more with my life than build other people's boring websites.

My advice to extremely bright and/or motivated high school students who have the option to get into the programming profession right away: consider whether this is going to be as intellectually stimulating in 5 years (or even 5 months) as it is now. There's no "right answer" to this question! But consider it carefully.

And don't under-estimate your potential.