Eew. Best of luck.
They dope you up enough that it's not uncomfortable. I don't remember a thing after the laughing technician.
FWIW, I stopped eating at 9PM the night before my procedure, they stuck the camera in at about 8:30 AM. This was not enough time to completely clear my stomach of food, to the disappointment of the doc. I would suggest more than 12 hours of fasting before your procedure for best image quality.