I felt fine, but BMs got annoying. I now eat twice a day just to keep things moving. And coffee.
I can't say I notice any difference at all in how I feel or weight or anything.
TBH, I don't really consider anything like the above fasting, and have only really fasted I guess once, when I was having a rather bad stomach issue. Day 1 was pain. Day 2 was lethargy. Day 3 felt like some kind of enlightenment. Mentally awake, but I was weak and my brain cloudy. It was a strange feeling of being mentally active but not able to really do anything with it. Maybe my body was giving me faux energy and alertness to go hunt with?
It was interesting, to say the least, but I haven't made a habit of it.