Huh? Before I went to college I use to stay up for around 3 days playing online games, from my own experience I can say that the only times I can really recall hallucinating is when I was playing FF Online back then and I was playing but I was looking at my hands while playing (PS2 version) and I remember recalling looking at the chat battle logs and able to see when refresh ran out on the paladin and white mage or black mage or whoever was in the party. It was like my mind was so fixed on doing the same repetitive action that I unconsciously got the timing down perfect as to when the refresh buff was running out.
I also do remember one night of doing drawings and I have a pet peeve believe that if I go to sleep before doing a really good picture I will lose all the motivation and energy to finish it the next day, so I stayed up for around 4 days drawing something and looking at blue orbs flying all around my room… probably being at the computer so close for so long. There us also that annoying thing as to when your eyes have blood on them and itch and every time air hits them you want to blink. Energy drinks make me go to sleep really badly, but the energy shots seem to work pretty decent if you get the right ones, I do recall those extended me for some hours and I didn’t have a crash effect afterwards.
The aftermath for me is normally really deep sleep and then waking up feeling weird, like my body has extra weight or something, but my mind feels light headed and I normally am sluggish for a few hours, I miss those days. Anyways, it really will mess with your sleeping habits, my only way to fix that was to force myself to sleep during the night so I wouldn’t end up waking up at night like I normally do if I where to stay up like this again. And… doing something you truly absolutely enjoy will help you stay up, I use to lose track of time playing online games and the sun annoyed me at around 6 a.m, btw the sun will hurt your eyes too. This is just based on what use to happen to me it might be different for you or something.