24 hour urine collection

My dr has me doing the 24hr urine collection bc my bp went up a bit. Started this am and I'm already over it. On the plus side, got a day off of work to do it so I can just relax! Anyway, just curious if anyone else out there has done it and can share experiences. I don't want to assume it'll be positive, but I've noticed most people they even ask to do it end up being diagnosed w pre-e....