I had it done when I was younger and that shit is no joke. Its bad enough I was caught off gaurd thinking my doctor was gonna do it then next thing I know this nurse walks in and is like 'Im going to help you today, your doctor isnt here". so Im sitting there trying to wake my shit up cuz I wasnt really prepared for a her. but I'll tell you right now, as soon as that bitch stuck that shit in the tip of my dick, there was no way I was waking up. that shit hurt so fuckin bad...and even worse, they dont just put it in. they move it around and scrape the inside of ur hole so they can get a sample.
im hurting right now just typing this. good luck homie. might be the worst experience of your life. but def better then gettin caught up wit an STD.