If you have not experienced weight-loss recently this is quite unusual, however slowing down of weight loss can be perfectly normal and happens to most dieters at some point.
It is very useful to keep a record of body measurements as well as weight because you can still be losing inches when you think that you are not losing body fat, if you are exercising more you could be losing fat but gaining muscle and muscle weighs more than fat which is another reason why it's not all about what the scales tell you!
You also need to take into account "the time of the month" as ladies always gain weight at this time due to water retention.
If you are consuming less calories than your body needs for energy then it has to use your fat stores for it's energy source but the first reaction will be for your metabolism to slow down to try to hold onto the fat which is why gentle exercise and drinking water is such an important part of the plan as both of these will help to speed up your metabolism.
Please try and keep a record of your calorie intake in case you are unknowingly exceeding the normal allowance.If you are confident that you are following the plan and keeping your fat and carbohydrate consumption low, you could also try to increase your activity levels which will definitely help burn those calories.