I think eskie is spot-on when describing this situation from a DBT perspective.
I also agree with a lot of what Chris is saying. In order for your T to help you he has to help himself, as well. If your T isn't at his best, his mind is preoccupied, or there are other circumstances going on that prevent him from giving you his full attention, then it was probably for the best that he rescheduled for a later date.

I think this situation says a lot about your T. It sounds like he cares about the quality of service that he gives to you. I think the decision was made in your best interest, but I can definitely see how it triggered you.

It might be a good idea to bring this up the next time you see him and let him know how it affected you.