I would advise telman17 to immediately go on vacation, at least for three weeks. Don't play a hero, the quicker you address this issue, the less damage you will do to yourself. Don't wait until it's too late. The brain is very fragile, and your livelihood.

Burnout is an awful thing. If your whole life is built around intellectual work, becoming something that has a cognitive ability south of a vegetable is a terrible thing. You lose your identity. The way back from there is long, my friend.