I've been at the same weight for 21 days now. Initially I was excited because I lost the requisite 5 pounds of water weight and I was happily waiting for the 1 or 2 pounds a week (hopefully). But I stalled almost immediately. I was stuck between 218 and 220 for 21 days.
Yesterday, I was at 217.5 and I thought MAYBE I had broken through the plateau. But this morning, it's back to 218. At least it's not higher.
I weigh myself every morning so I can keep a 10 day running average of my weight, and that's what I use to gauge my progress, not the actual number on the scale, because it can fluctuate by 2-4 pounds in a day.
I've upped my fat content in my diet, cut out all processed foods except the 1/2 protein "brownie" that is my afternoon snack. I'm eating plenty of veggies. Still have a decent amount of dairy in the butter and an ounce or so of cheese every day. I'll stick with this for another week. I've been slowly trying to add in more daily exercise/movement.