Cute girl, our gym is full of those, CF makes girls look amazing.
As far as the warmup goes, when i first started CF it tore me up, hell i was just doing 3 sets of 8 and then the baby workouts. After two months or so all it is going to do is get your blood moving. I now do 10,12,15 reps for the warmup and then jump in to the WOD.
CF will make a beast out of you, no doubt about it. Not to mention it makes girls simply stunning. I would say that 75% of the people in our gym are girls, i simply love days where we do wallball or deep squats