What else is there to do? If you don't get the huge loss you're wanting what are you going to do? Stop the diet and either eat rubbish cos you're fed up, or go onto another diet? The VLCDs (Cambridge/LL/Lipotrim etc) are the only diets that let you lose weight this fast. If you've been 100% then your body will lose 100% of the weight it wants to lose this week, that's all you can say. Giving up and getting miserable about it will get the weight off slower, not quicker.
I know it can be hard wanting it to happen overnight, but we put the weight on over several years, wanting it off in days is unrealistic. I think we have to go through the journey so we reprogram ourselves. At least our journey is going to be shorter and hopefully more informative than a journey on WW or SW for instance.
I lost 10 lbs on my first week, but this week so far I only seem to have lost a couple of lbs. There's nothing I can do about it except keep drinking the water. Good luck for your weigh in, all you can do is keep going and doing your best, the weight has to come off, but it'll come off at its own pace.