Really nothing you could have done differently that would have improved your chances, given the time frame (Wed-Sat). You got a really good combination of sleep and acclimization. Not sleeping at the campground is par for the course and leaving at 2:00 was the right call because you're probably just going to lie awake all night in the tent anyway, and besides you needed the extra time to do the hike in case something went wrong (it would be no fun to try to get down in the dark being totally exhaused).
What really went wrong is probably just your lack of experience and conditioning. The effects of altitude are not nearly as strong when you are conditioned as your heart rate is much lower so you don't need as much oxygen.
