ditto ditto ditto....
5lbs is fantastic, especially in week 2 onwards, I know I will definitely be over the moon if I lose 5lbs in week 2, in fact, Im kinda counting on it!
If you can maintain that level of weightloss every week you're going to be at goal in no time. Remember, a regular calorie controlled diet only yields about 1.5-2lbs weight loss a week so you are already losing more than twice as fast as you would normally.
Chin up, stick with it, and DON'T COMPARE!!! All our bodies are different, we have different amounts of weight to lose, different histories of dieting (which all affects our metabolism) and different levels of activity in our lives. Know that if you still to it rigidly your body WILL lose the fat and you will get to goal at a rate that's personal to you.