I had a lucid nightmare and one of the scariest parts now in retrospect is that after one of the false awakenings I couldn't breath through my left nostril because I thought I was laying on my bed in real life in a way that blocked the air. But luckily the right one worked fine. But still, it would've been terrifying if I wouldn't have been able to breath at all.

Has anything like this ever happened to any of you?
It's the only time the nose plug reality check didn't work. (for me)