rsl12 When I showed the video to my teacher, the first question she asked was "when is the last time you got your piano tuned?"
In the meta thread about this recital, we discussed how big swings in humidity/temp likely threw it out of tune since the last tuning in October. And now my soundboard is cracked too, I think I mentioned that in the low humidity thread.
Anyway... my house has a humidifier system now, the humidity is steady at 40%, and I'll probably be able to keep it more in tune between tunings going forward.
On your and @Nightowl comments about the flat E. Could be my embouchure. The tuning slides are pushed all the way in so I can't make it sharper. I don't have perfect pitch, so I just need to work on improving my tone.
Edited: on your comment re: concert pitch, when I learned in school I only knew bass clef. I don't conceptually understand the difference between the notes being different in treble vs. bass, since I never learned treble clef prior to learning how to play piano.