How to prevent self harm in cnc (tw: cnc and ed)

Hello all! Im am very very into cnc and love being hurt. However, I ran into an issue during my last session.

It had been a while since I had seen my partner and he was choking me hard. I loved it. It felt uniquely impassioned. I would tap his arm and he would choke me even tighter. I loved it. However, I have a habit of ignoring my body's danger cues. I am a survivor of an eating disorder and have a history of ignoring hunger cues until it gets Bad.

In that moment, I stopped the scene because I realized I hadn't formally set a safeword or movement. My dom and I are relatively inexperienced in kink but he always leans on the side of caution. He will let go and give me air whenever I said stop, but i know that isn't a good rule in cnc. I ran into two issues.

The first one is the classic issue of "what is a safeword or movement I can use that won't break the energy of the scene, but is a hard stop?" I truly dont know what to do in moments where I am choked or tied up. I think my save word should be "T" like time out, but im worried that's not good enough. I also wonder if I should have two safewords. One that I can use frequently in moments where I need air, and one that means Stop the scene. I truly dont know what to choose or do.

The second is that I genuinely had a hard time stopping. I was so aroused by the lack of safeword and was so into my needs being ignored. I love the idea of putting my life in someone else's hands. However, where do you draw a line when you can't trust yourself?

Need any and all advice!