Two things:
1. Vis a vis the lack of weight loss, I would suggest ramping up the exercise a bit. I feel like my weight loss really started accelerating once I start pushing myself harder on the treadmill and elliptical. I'm sore, but it's worth it. You can't out-exercise a bad diet, but it really complements a good diet.
2. Absolute weight numbers are basically meaningless when it comes to weight loss. As someone else noted, if you start out at 200lbs, you are not going to see the same absolute numbers as someone at 500lbs. You should be looking at your starting excess weight on the day of surgery and seeing how you're progressing from there. For example, I was 302lbs, my initial goal is 170lbs. Thus, my excess weight is 132lbs. I've lost 34lbs thus far, so 34/132 = 25% of the excess body weight is gone over almost exactly a month. It's unlikely I'll be able to keep doing that, but it's super encouraging for now.