I've been looking at your fitday stats and I do have some comments on how you could make a change.
But first of all your loss looks good when you see to the %. Really!
I saw that your carbs come from various Atkins products and that you use Splenda. Maybe you should cut those for a while, have you been using them all the way or just recently? More veggies could do the trick, I saw very little of them in your menue...we really need them and we need them fresh!
I also agree with the others, you might be gaining muscles!
Don't know if you're on any medications? Also, I gained 3 pounds the week before my TOM both times since starting Atkins.
Check out my fitday if you want.
Good luck!

Alina