Difficulty breathing - can't get enough air through nose but it is not blocked
I am 29, and about 60kg overweight, generally healthy (despite the weight)but I have PCOS and a few problems related to this. Also get mild asthma during cold weather or when I have a cold/flu.
I have (once again!) started trying to get more active and went for a 1 hour walk this afternoon. It was not fast, and I could still maintain a conversation with my friend, and the heart rate wasn't up too much, but I was a little breathless, which given my weight doesn't surprise me. The embarrasing and scary thing though is that I can't seem to get enough air in through my nose, so I am breathing loudly - I either gasp a huge breath in or have to yawn. This has been happening to me for a few years when I do any kind of physical activity other than daily routine (I am a teacher of 6 year olds so I don't just sit around all day though). Aren't you supposed to breathe in through your nose and out through your mouth when exercising?
I kept trying to breathe quietly though my nose, but its like the air does not make it past the back of my throat/back of nasal passage, whereas if I yawn or do an open-mouthed deep breath in I can feel the air going right to the bottom of my rib-cage. Why is this? My nose is not blocked, no noticeable congestion - it has been sort of 'bogging' up sometimes like its swollen and I can't breathe through it at all sometimes, but no mucus other than I have to clear my throat a bit, I thought maybe an allergy, but it was ok today - and I had taken my asthma puffer before I went on the walk just in case. (Sometimes when I am sitting and doing nothing I will do the yawn/deep breath thing every now and then, but when I was walking it was frequent)
Any ideas? Could I have some kind of nasal blockage that is more noticeable when I need to try and get more air in during exercise?
Thanks for your help.