Caffeine easily creates a negative feedback loop where you consume it, then get less and lower quality sleep, and therefore need more caffeine to function at the same level, so you sleep even worse, and so on.

The main fixes I’ve found for myself are:

- Get a lot of exercise and sunlight (if possible) to counteract the caffeine’s effect on sleep.

- Resist the urge to have more caffeine than usual when tired. It works well as an enhancer to a well-rested brain, but when used to compensate for sleep deprivation, it’s counter-productive.