Exercising is it's own reward

That is what I keep trying to tell myself, or convince myself. After three weeks of regularly exercising, the scale hasn't budged. Maybe it is the ice cream for a snack when the kids are napping, or the cookies for breakfast.....do you think? It is time to cut back. I was hoping that jogging three times a week would do it and cutting back on evening snacks. I guess shifting around my calories to earlier in the day, doesn't do anything.