The non yoyo yoyo diet

So a couple months ago I decided I wanted to lose 5 - 10 lbs for my race next month. The only way I have been successful lately in losing any weight was to track my calories in and calories out and make sure there was enough of a deficit to actually lose weight. So for two weeks I wrote down everything I ate and logged all my workouts calorie expenditures and had 500 - 1000 less taken in then going out. I should be about 3 lbs less, but to my dismay I was the same body fat % and weight. After all that time and energy into planning meals, eating the right kind of foods, cutting the calories. Nothing, nada, nicht, mola. So for the next two weeks I decided to not count calories or plan or keep track of anything. Just eat when I was hungry and eat what I felt like eating. I didn't go out of my way to over eat, or eat junk food. I normally eat fairly decent anyway, but there was no deprivation. If I wanted M&M's, I ate them. It was great, I had more time, did less thinking, wasn't hungry when I went to bed. After two weeks, same body fat % and weight. I just don't get it.