Sounds like you are doing everything great! Remember it will not be a reg. bowel movement that you are use to having while your on the cleanse. It is liquidy......which sounds like what your having (that is normal for being on the MC)
I'm just off a 30 day cleanse and I had the liquid movements in morning then pee the rest of day.......that is fine. 3lbs. is fine....everyone loses at a different rate, as the day's go on you will see more. I wouldn't worry about water retention unless your face or feet are swollen . From what you wrote it seems like you are doing Wonderful. Keep doing exactly what your doing your well on your way to your goal!