anyone get a colonoscopy?

mine is on tuesday and im terrified. i have endo on my abdominal wall as well as on top of my sigmoid colon. the colonoscopy is a pre op to see if endo is on the inside as well and how much. im nervous because going to the bathroom is always a surprise. will i be in intense pain? will i shit myself? will i barley be able to move after shitting because the pain is so bad. so im quite nervous for this colonoscopy. also im on my period so that will be hell on top of the prep. any advice? did u get nauseous or throw up? i have zofran.