I had finished squats, and I'm in my first set of deadlifts when I feel and hear a snap! in my lower right back area. Not quite into the glute region, but close. My second thought was--because my first thought was, "Holy crap! What was that?"--was it really pain or can I work through my other three sets of deadlifts?
I did not work through more sets of deadlifts, because that would be stupid. I immediately grabbed the ibuprofen and an ice bag, wedging it in my workout clothes. Later, Dale would tell me I had a wet spot on my rear end and I would shoot him a does-it-look-like-I'm-concerned-with-wet-spots-on-my-rear-end? look.
Leg Extensions: 90#/15, 90#/15, 90#/12
Squats: 45#/25, 65#/20, 85#/15, 95#/10
Deadlifts: 95#/12 (should have stopped at 11!)