Awe, well, please don't judge yourself for what you've said and your worries: she bungled a bit by forgetting something so important and you were upset, very reasonably, and she seems to be willing to make amends. I think that's the way it's supposed to go!

At the risk of sounding hypocritical, haha, I will admit, I've definitely been there- getting upset, showing it, then feeling ashamed of myself, thinking I got "too" upset given the situation, but you know what... a great part of my therapy has been having my therapist validate my feelings, understand my upset, and she has always been very gracious about patching those ruptures up, so I feel comfortable coming into session after a snafu like this, so maybe it won't be nearly as bad as you fear if you go tomorrow.