The OP is probably an extreme case, but the most important thing for YOU is to take care of yourself.

You're probably just lacking sleep at the moment (when I work crazy days like that, I have codemares, which means my mind never really gets a break from coding). You need to unwind properly this weekend, or whenever your next days off are.

Also, I'd recommend telling your boss how you're feeling, and what you've put yourself through. He might not understand, and may be surprised at how you're feeling about it, but you don't want him thinking you came in as a rockstar and burned out in a flash. You want him to know he can rely on you when things get rough, as they always do, but that you can't push yourself endlessly.