SUGAR ~ well, it does seem odd that as soon as you started this fairly rigorous exercise program -- that weightloss stopped. While, it is possible you are still losing some internal fat and recompositioning (fat to muscle ratio), it is possible you may be overdoing it a bit. Sometimes, it is better to start slow and work your way up.
And, you can gain some weight doing all that weight-lifting: I know I gained 9 lbs one year without any other change but I did lose 2-3 sizes and dozens of inches everywhere. You have a few options -- 1) wait a while longer; 2) up your food intake a bit; or 3) cut back your exercise to every other day ... focusing on walking, weights, and toning only to see what happens. Many people lose weight that way.
Since it has only been about 4 weeks, you could wait a bit longer; or just go ahead and try something else. I have seen this happen before. You will get long-term toning benefits from your routines, and feel stronger -- but WL benefits may suffer a little (stall).