Can I ask you how, and why, you do this? I'm genuinely curious as even back when I was your age I would be fatigued after maybe half of that time.
As others have said, this exaggerated workload obviously contributes to your situation.
Sure thing. I'm a dropout, I have plenty of time. I'm not sleeping much, most days 4 hours of sleeping is enough for me. I don't know the exact reason why, how I feel deep inside, I just enjoy what I do and I never felt fatigued till now.
The root of your problems is something else though. I like science, so this helped me more than anything else: https://www.youtube.com/watch?v=NqtYZJSGeEY.
Everyone will suggest professional help, and you should seek it if you're comfortable, but the Internet has everything you need at this point. I'm sure your adventures have trained you in the Art of Googling.