Welcome to the addiction and impending slippery slope of track mods.  
 
It's great that you have your wife DEing too, as that's a great way for a spouse to understand the addiction.  My sister always rolls her eyes when my brother and I discuss track days.  She did some parade laps at COTA in May and now has an appreciation of what we do.
It's amazing how prepared you feel you are before a DE but can still have a sloppy 1st session.  It takes a certain amt of time to get into a rhythm.  Taping your runs is a great way to learn.  You'll see so many places to improve.  That creates a burning for the next DE.
12 days until INDY.  Can't wait.