I was attempting to discard Architectural improvement. Instead, Saints-day was played. On my next turn, I successfully discarded Architectural improvement as previously attempted. That's all I can recall for certain.
I don't know. I want to say I may have clicked the wrong card, except that I used the drop-down menu and know that it was the button beside it that I pressed. I wouldn't have selected the number and then floated over to an entirely different card.