Well, it's not a rule that you stand in front of your mirror and no smirks allowed...that is what your T wants.
Any time you can counter a negative, whether in front of your mirror or not, or whether you giggle about it and really don't believe it or not, it will help to counter them (the negative thoughts.)
No, you didn't make your T cry.
Since it was such a short time, IDK that her rescheduling would have done any better for you. I do think her leaving the room for those minutes would have been better.
Getting upset at yourself, and certainly if you had become angry, well that wouldn't have been good either. I think you've realized that maybe it's your sensitivity that made this appear so large? Of course, that's part of why you are in therapy, I'm sure, so if you wish to discuss that aspect of this with your T, and make it a good therapeutic session, that would be good, imo.
Few people would have acted outwardly, any different I think, especially given the short nature of the incident. Yes, Ts are to keep their personal lives to themselves, however this obviously was an "at work, happening now" issue, -and- your T is human (who knew?) so it's really up to you as to whether you received any benefit from your session or not. You did say you numbed out (started to go away) and I am concerned that perhaps her rescheduling might have been better for you.