I think it's more that she was vaguely irritated by being "ditched" (though you didn't do it on purpose, it's a valid thing to be vaguely irritated about) but then the gleeful tone of your entry detailing your superfunhappy activities that night that really sent her over the proverbial edge. (At least that's what would've done it for me.)

None of the above comes from Shawna in any form; it's just me extrapolatin'.

It just makes me mad to see you two feudin', cos I like you both!