Men always lose a lot faster than women. The average loss on this diet for women is 1 stone a month which is roughly 3lb a week. Although, one week you may loose 5 or 6 and the next only 1-2lb. The time of month will also affect your losses so jeep an eye on when that comes about and what your weight loss is, that will help you predict your future weight losses.
Pease don't worry too much. At the end of the day, as long as you are being 100% the weight will come off,
Good luck for this week x x