Yeah, I know how that goes. I'm the type to stay awake for more than 20 hours only to find myself in desperate need of sleep yet unable to focus and empty my mind. Just a few days ago I was awake for 38 hours.
@Undine Damn. I need to take meds to sleep well, and if I don't have them, well... I struggle to sleep. And if I'm awake for more than 24 hours I lose coherency in my thoughts. That's when I know I need sleep bad.