Originally Posted by emma69

I get similar moments, but at ground level, so no oxygen level issues, and I suspect (as does my doctor) they are little panic attacks (but I am not 'panicked' about anything consciously). They tend to happen in more crowded areas, like a train, so I think my subconscious is telling me 'get away from all these oxygen suckers' or summat like that.

Originally Posted by gobluetwo

Agree with Emma that it's likely not an issue of oxygen levels, but some other physiological response to your environment.