Depression can hit this way, too. You can be apathetic towards everything, no motivation, stuck in your head. It can be easy to get caught in a downward spiral, trapped in the vortex of negativity you no longer feel in control of.
The apathy is probably the worst part. Like, I know this thing I need to do is important and that not doing it will have some very negative consequences, but I just don't care enough to do it. Then, last-minute panic sets in and I half-ass it, which is still good enough, but it hurts that I could do so much more if my brain wasn't malfunctioning like that.
Been me the past couple weeks. Why bother eating. I'm not hungry and don't feel like it. Why bother getting off the couch, I've been here for the last 36 hours and it's not like something's magically happened that's worth getting up for. Why even bother killing myself, if I just lay here long enough it'll happen eventually
This is why I like weed. It's not so much the body feel (though that is a nice bonus), as much as it quiets my mind and allows me to have some fucking peace and quiet in my own head.