"That was just the warm up?"

I attempted to do one of the INSANITY dvd's at lunch today with several people from work....During the first part of the workout when I was dying and my feet were bothering me...one of the ladies yelled, "OMG...that was just the warm up!" It was so very interesting and so very cardio filled. But I have to be honest, we started on the second level...and I can comfortably say...I should have started on LEVEL 1!