How do you experience breathing problems?

Hi, I was hoping you could share what breathing problems feel like for you.
For me, it's mostly feeling a pressure on my chest and lightheadedness/feeling like I'm about to faint.
But I don't experience anything like wheezing or appearing out of breath or something like that. This makes it difficult for me to search medical help for it, since it's all just 'feelings' instead of actual visible signs of breathing weakness/difficulties. Sometimes I randomly start sighing deeply, other times it feels more like my urge to breathe just becomes almost absent?
Is this familiar to any of you?
Thanx in advance 😀