Don't let them scare you! Mine was a lot less painful than I expected. Just a little *weird* feeling. Kinda crampy when they put the dye in... but not painful. I took Aleve before I went in, starting the night before. When it was done I felt 100% fine after. Well besides that black gunk coming out on the panty liner. EWW (Iodine I guess?)
Good luck and I hope you post tomorrow saying it was a piece of cake