Losing at Losing?

First, let me tell you a story about two young women who work in a bakery... :)

           One day, in about mid august, two friends (who work in the same bakery) decided to make a deal. This deal was not like any other deal they had ever made before. It was almost like a pact. A pact to do something with our lives. A pact to lose weight.
           The deal was that the one who lost the least amount of weight, before a certain time, had to buy the other one a trip to the movies.
           I don't know how to lose a lot of weight other than through exercise and dieting and I seem to have stopped losing weight all together.
           I lost a few pounds in the first week, followed by a few more in the second week. It's the beginning of week three and I'm not even close to losing the amount she's already lost. I've lost about six or seven pounds total and she has almost three or four less than me. I'm getting extremely frustrated because I'm practically eating nothing and working out constantly. I've done more cardio so far this month than I think I have in my entire life.
          I am not going to resort to diet pills or anything like that... but, man, I sure have thought about it. 
          I'm getting tired of being obese. At least, that's what my Wii fit tells me (in a happy, cheerful tone(bitch)).
          Any suggestions on how I can shed weight? I'll definately share with my friend. Even though I want to win, I'm not going to be a jerk about it. :)