I know this thread is a few months old, however, I can tell you that I was over-training and recently got a fluke ankle injury. Here's what I was doing per week 2 salsa/dance classes (total 1.5 hours) 2 boot camp classes (total 2 hours) 1 cardio kickboxing class (total 1 hour) 2 Muay Thai classes (total 2 hours - 50% technique/50% cardio) 2 hours volleyball (total 2 hours) 2 hours yoga (total 2 hours). I was doing this for about 6 months. Luck finally caught up with me.
Everyone is different. One person's routine might be right for them and overtraining for someone else. One of the best indicators of overtraining is loss of interest. Add to that tiredness and general fatigue. If that sounds like you, it's time to change the routine for awhile.