Diversity schmersity

So I got up extra early yesterday morning & ventured down to the Excalibur to go to this 'diversity class'... I get there, and the class isn't where it's supposed to be. Me, a bellman & a guy who looked like an off-duty security guard are all standing around in HR while the HR rep calls around to find out where said class is - it's up in the 3rd floor banquet halls. So we trudge up there. And the woman literally yells at us: "You're too late! Tell your supervisor to reschedule you!" It's been a long time since I've been yelled at by another adult in a professional setting - I was taken rather aback, to say the least. I'm volatile & grumpy, sometimes I snap at people, but I don't raise my voice & holler. When we showed up at the classroom door, everyone turned to look at us, but when the instructor yelled at us, everyone turned faster to look at her. The bellman went off, and I thought about it but decided not to disrupt the class any further than the instructor already had. So I know when I actually get rescheduled to take the class, if it's the same instructor, I'm going to think a lot less of her. She probably won't even recognize me - but I'll definitely remember her. If I'd felt like it, I could have gotten her name & filed a voluntary against her but... I decided better of it.