The oxygenation level is a thing that I worry about. My breathing gets really strange, I draw in a really fast, short breath, then breathe out very slowly, over the course of like... 10-15 seconds. The inhale to exhale ratio is probably 1:20. Maybe not in terms of oxygen in/c02 out, but certainly based on time.
If you have the awareness to notice your breathing like this, you are not likely in any kind of physical danger. Good to have someone close. Cold water could help too, even if you can only sip. I find sounds and sound vibrations on my body help...I can't move but can "access" that somehow internally and it helps shift the freeze so I can slowly pull out. I keep tuning forks with me.