Were you able to talk to them at all about what happened before you left the session? I would try talking to them about it and hopefully they can be honest in how they feel about working with that.
I know last week I had a really strange dissociative reaction with my T (I disassociate a lot but this felt completely different) and he reacted in a way that intellectually feels strange to me. I don’t know how to interpret it at all... if he was worried, uncomfortable, confused... my behavior was not anything he had seen from me before. We didn’t get a chance to talk about it as it was too close to the end of the session but I am sure we will next week.