Yeah it's possible you're gonna puke. I'd give yourself at least one day of adjustment period, no matter how tempting it is to wolf down macaroni and cheese.
Coming down off a fast is just about as hard as fasting after eating a corned beef sandwhich. It feels nasty. If I were you I'd start on Wednesday morning with some diluted glasses of fruit juice. For lunch have a fruit salad and for dinner try some steamed vegetables with juices. That's awfully rapid but it's better than just going straight off it which will make you sick. You'll still lose weight eating the fruits and vegetables so don't worry.