First colonoscopy at 23 !!😩😩🥵help !

So Thursday I went to the gastroenterologist and he suspected that I had hemmeroids so he suggested I’d get a colonoscopy which I’ll be doing Tuesday afternoon. At first I was worried about the procedure and being asleep... then that became the easiest part for me and now I’m overwhelmed with the colonoscopy prep part... I’ve been instructed to take 3 dulcoLax tablets and a split dose of 64oz of miralax ... I’m so terrified from hearing so many colonoscopy prep horror stories like vomiting and not being able to keep the miralax down after just one cup or having violent diarrhea or passing out from dehydration... I’m so petite and so scared of vomiting that this whole procedure makes me nervous. Does anyone have any hopefully comforting experiences with colonoscopy they can share ? 😩😩😩please LOL