Ok...don't panic. It's just a small hiccup...2 kgs in the first week (is that right?) is amazing. Perhaps some of it was just a fluid loss though and now this week may be a better reflection of true fat loss.
If you keep doing what you've been doing the weight has to come off. Make sure you are drinking plenty of water so there's no fluid retention. Also check there's no hidden salt in any of the foods you're eating.
Chin up and chest out, we're in this together, the dog loves you and needs a walk. Oh, and by the way....you're skinnier than you were two weeks ago.