This sounds exactly what happened to me. Natural progression of the diet I think. I had a stall during my 4th week. I was staying the same weight and even fluctuating a bit higher and I was very discouraged! My week 4 weigh in I lost nothing- just 5 inches. Then my week 5 weigh in I lost 5.4lbs!
My advice:
I know it is very hard not to step on the scale. I do it daily too- so instead of telling you not to step on the scale- go ahead and do it, but don't let it discourage you from moving forward and sticking with the plan!!!!!! Just move on! lol
Secondly, I agree you should have your 3rd pack. Even if it's only a drink- I LOVE the Dr. Bernstein's RTD chocolate, tastes like rich chocolate milk! And they are soooo much cheaper than the IP version (12.00 for 6) and have exactly the same nutrition stats.
As far as the ketosis sticks- they are not reliable enough to base any sort of decisions off of them. The body is so complex physiologically there isn't really any point in using them in my opinion...there are so many different things that could be going on that would make it a false positive or false negative.
Take home message- just keep doing what you are doing, and the scale will move...I promise!
And as far as the cravings- I have found that at first I didn't crave anything, and now I kinda of do occasionally..and then not again. It's kind of unpredictable and comes and goes!