This really was absolutely the *wrong* session for him to happen to not read the material. I'm so sorry it happened and has left you in this place. You needed him to be beside you where you are and to understand what you are going through and be safe. You still need that, I think. I know this has thrown you into a very isolated and frightening place, but I'm wondering if you can still maybe put one hand above water and keep texting him. He is a representation of half the species, but way above and beyond that he's your T, who has been safe for you, and I think would do anything to be there for you and help you get through this.
Yaku, there is *nothing you can do to turn your T into a bad person*. You don't have that power. He is grounded, ethical, and cares very much about doing right by you and all his clients. If what is going on for you right now is the belief that you make people turn bad or hurt you, please know that that is a lie you were told, in words and/or actions, by some very sick people who did not want to take responsibility for their own actions. Please don't believe that lie - it is just a form of their sickness.
Hang in there. For hyperventilation, breathing in for two counts and out for four may help.