...I was so caught up in passing my own best of 60 feet that I did not pay attention to the air gauge as much as the depth gauge.
Never treat "depth" as a goal, objective or benchmark to the point that you pull your attention from ANYTHING else..
However, I'd also love to know how you went through 2k lbs of air on a descent. Did anything else happen that you are leaving out? Equalization issues? Gear issues? Anything that paused you? If not, you really should check your gear for malfunctions (leaks) and pay more attention to your pre-dive check with your buddy. Having done so would have solidified your buddy's knowledge of your air level - to which should have been the level being used for the planned dive.
Glad you're okay.