Ugh, sorry you went through that. I've had full-blown panic attacks in sessions with my individual T before, where I've come close to asking to leave or at least go to the bathroom because I felt sick. A couple times, she asked if I wanted to do a relaxation exercise (like closing my eyes, visualization of something calming, etc.), and we spent the last 20 minutes of the session on that. It helped. And sometimes when T can tell I'm really stressed, I'll end up talking about something fairly off-topic, like childhood pets or my H and I's wedding, and she'll just let me go with it for a bit. It's like she knows I need to discuss something lighter rather than other stuff. (Of course, other times, she knows I'm avoiding and will steer me back on course.)
Maybe you could ask your T to do that for you? I'd certainly let her know the intense effect that session had on you. i think you telling her that alone should lead her to give you a lighter session.