The glass door: I wouldn't do therapy in a room in which people could see me, but if it was frosted glass and no one could see in, then I would be OK with it. But I don't think the T you were there to see has this room, because none of the other rooms had glass doors. If that T who was there had been your T, surely she would have said something? So I don't think it was her and she most likely has a non-glass door.
The noise factor: do you think the non-glass door rooms would be more muffled?
Should you go back? If all other things were equal, I probably would, as I am very forgiving (a fault at times). For me it would depend on how positive I was about the other 2 therapists that were scheduled. Isn't one of them the therapist who asked a lot of personal questions on the phone? And that made you uncomfortable? Seems like that is a "sign" against her too. Who is the other one and how did your phone convo with her go?
If I had had a really good impression of the Reiki T over the phone, I would probably try her again. Stuff happens. I would talk a bit about it and tell her it is really hard for you to reschedule on short notice due to your childcare situation, and ask if that happens a lot.
I'm sorry it worked out so poorly today, BlueMoon. I guess you are expected to call her back and tell her if Friday will work for you. Hard decision... I could see it going either way, depending on how favorably you are viewing the other 2 Ts you have scheduled.
Good for you to meet with your friends.