It's always a little funny (I can't think of the right word) to me when I read posts of people thinking something is wrong if they are losing weight at a rate of only 1/2-1 lb/week. I have lost 38 pounds by losing an average of 1/2 pound a week. You just have to be patient! Losing 2.6 pounds in 3 weeks is a healthy rate to lose weight. You could lose weight at a faster rate if you only went over your calorie range 1-2 days a week (or less) instead of 4, if that's something you think you can commit to.
Basically, don't be sad!! You've obviously made progress in eating healthier, and beginning to work out as well. Losing weight is a process and it's not going to happen overnight, and it's not going to happen in a week. I look at it this way--I didn't gain 45 pounds overnight, so I'm not going to lose it overnight either!