Day 1 for me was yesterday and I had tons of physical withdrawal symptoms. Shaking, sweating, chills, nausea, worried feeling, dizzy, and more. Last night, I barely slept. I woke up every 20 minutes and had so many night mares.
Today's day 2 and I'm managing a bit better. I'm eating normal and drinking water more. Headache, mild shakes, and still feel hot.
It's quite different for everyone. One time when I "quit", I would feel like passing out every time I stood up. And I think I did a couple times. I am not sure if that was due to dehydration or the complete lack of nutrition. When I go on benders, I don't eat and just drink.