You may not want to make it so you unconsciously orchestrated being late so you could quit therapy What happens isn't about your therapist, it's your therapy and under your direction.

I'd call/get in contact with your T, in person, rather than wait to see if he gets in contact with you, make another appointment, etc. or tell him you will not be returning because you don't wish to work with therapy anymore, get his one-on-one viewpoint instead of guessing by e-mail return/no return where he might stand.

Presumably, you knew you were going late before you were; I would have pulled over and called T to let him know? It's a joint effort, therapy; being late is one thing but not letting your "partner" know shows you don't care either? You could have solved it on the phone, rescheduled then or asked him to wait, etc.?