My thoughts would expand like a fractal and it would take active effort to make it all the way back out. I probably can't really communicate it to someone who hasn't experienced psychedelics before, but it makes me feel like I am conscious of every bit of mental effort I am spending. Pulling myself out of deep thought feels like a long, manual process, even if it's actually instant. An analogy I liked to use is having to arrange all the neurons manually or something.

After every instance of that, it felt like I had spent so much time in that fractal that it was difficult to recall what had happened previously. It's not like ADHD where I get distracted and lose something from my short-term memory—it's that I had so many other thoughts that it was difficult to backtrack past them all.

This happened to uh a friend the first time they got really high on weed.

It's just a trick your brain is playing on you man. I was playing Rainbow Six Siege with friends, and during the 30 second setup phase I played for what was surely several minutes doing all the things you do with the drone and looking everywhere and planning all sorts of things, and then I looked at the timer and only 5 seconds had passed.

Your brain's interpretation of time passing is a completely made up fiction for it's own benefit. Police officers report seeing shootings going down in slow motion, watching individual shell casings drop to the floor and reading the numbers stamped on the bottom.

When this kind of time dilation was scientifically investigated, we found that what actually changed was your MEMORY of that time, not your cognition during the dilation itself. You aren't actually experiencing things quicker, your brain is just timestamping stuff poorly. Your brain's time tracking system just gets out of whack, and that screws with your consciousness because it relies heavily on timestamping of things.