You are doing great! You are succeeding...keep it going. I am not an authority, but I think a typical pattern for most people is that during the first weeks, the pounds come off quickly and then the following weeks, the rate of loss slows down.

Don't stop. Here's some things you could try:
* Change Exercise routine - add some variety to the exercise you are doing to work different muscles and keep your body from getting too adjusted to the one exercise you do frequently.
* Weights - try doing using some light weights to work your muscles. Strength workouts are a great way to burn more calories.
* Move more - take breaks in your day to walk around, use the stairs, add any thing that keeps you moving around during the day.