What is the relationship between feeling too warm and lung disease(s)?

I finally went to the doctor when my episodes of the following increased to the point where I would sometimes have to lie down -- outside or inside a building -- until I was no longer dizzy. It doesn't follow what I knew/know about COPD/asthma (with which is what I was ultimately diagnosed about 6 mo. ago), but it must be related. What happens is that sometimes, with no warning, I feel very warm all of a sudden -- this is followed by nausea, sometimes lower back pain, dizziness and a feeling that I'm going to faint. I don't notice SOB but it must be there. Often, when this occurs, I've been standing mostly in one place for awhile and there's no moving air/breeze. Stress plays a factor also, I think. I've asked my pulmonologist and my GP and they say they don't know why this occurs. Can you help? It's frightening because I'm becoming more afraid to go do things in public in case this happens. A rescue inhaler hasn't been prescribed, but I assumed that if this required one, the pulmonologist would have prescribed one. ???