Congrats!!!!! Keep up the good work!
Weight loss isn't linear -- it seems that sometimes it takes a while for the fat to get the message to leave, already! It may not have been anything you did this week, but all those previous good behaviors. After all, you probably didn't have a 21,000 calorie deficit just this week (3500x6).
I think this is how the scale works! It's

It kills you when you plateau, but then you have great days like this.