Need more than the gym

Last week I decided to get my body fat tested since it had been since March. When i started the gym I was 183 (10lbs less than my heaviest ever). So I had lost 5lbs since then. Since it was only 5lbs since the last measurement. I knew it would not be much...I was right. I tested 23.9% ( a loss of 2%). I was disappointed that I had not utilized the gym to my full potential, but my trainer then asked, how are you eating? I reported that I hadn't really changed, and my weight has remained the same for at least a month. Of course I already knew this, but he had to kick me in the butt and remind me to eat right. So today I started weight watchers at 178.6 lbs and body fat % at 23.9%