Hiya, Linda. Look at you!! (shakes head in awed inspiration)
Stay the course, Medibud! Your weight WILL fluctuate throughout the week, and even throughout the month, depending on so many variables. The scale is only data; it is quantitative. Don't take it as a qualitative evaluation! There were weeks I'd get on thinking I'd lost and I was actually up a pound (or two). (Aim for at least the same weight -- my ups got a little out of hand a couple of times this year.)
And, yes, the loss slows down. My goal is a pound a week. Sometimes I exceed it, sometimes I'm not quite there. My favorite measures, though, are feeling my midsection and squinting at the size label in my pants.
Every three hours, you're changing your life. Make it a lifetime change!