Although the circuits are definitely helping you get leaner and more conditioned, I also think it's important that you work on your endurance. So, after you squat, I want you to hit the pavement, pool, or track for an hour of endurance training.
If you're not accustomed to long-distance training, today might be a struggle for you. All those reps of squats definitely won't make it any easier. But embrace it. Working on your weaknesses will only make you a better athlete and a stronger person. You've made a commitment to change. Today, you get to show you can follow through.