Ask HN: How can I get over my lethargy, lack of focus, and other problems?

I see myself as someone who's really interested in programming, and computer science more broadly. Like the kind of person who's into it more as a hobby than a career choice; I was almost one of those kids who start hacking when they're eight. But while I know I am really interested in that stuff, most of the time I just stare at the wall when I take my laptop to Starbucks.

Again, it's not that I'm not interested in it. Most of the time, I just have this insurmountable mental block. I don't know if it's depression, or what, but it's not merely a lack of energy. Many days I can barely even read; my brain just won't process the words on the page, or on the screen. The occasional, completely random good days I have are marked not only by energy, but mental clarity. Most of the time there's like an ugly fog hanging over my head. When that fog isn't there I'm a twenty-five year old version of that curious eight year old hacker, but when it's there I just stare at the wall.

I've tried all kinds of things, except professional help, which I can't really do right now because of reasons: vitamins, caffeine, no caffeine, exercise, meditation, not eating carbs, getting more sunlight. None of it works. Maybe someone can point me in the right direction?