Thanks so much! Yeah I think the consensus is that a tutorial of some kind would have gone a long way.
The feedback to have in there:
Breathing SFX for all actions (could be louder?)
Face turns blue if you hold your breath too long (empty or full)
Lungs meter/image expands and shrinks with breathing. Turns red at 0% and green at 100%
Face and stress meter.
The character could have had some additional animations to match the breathing.
I considered some kind of visual puff of air coming from the mouth but decided against it to keep it more "realistic" or natural haha. Maybe wasn't the right choice