What Could Frequent Shaky Spells While Having COPD Suggest?

I have these spells . I am 60, female, overweight, COPD/Emphazema. These spells start with a kind of weird wa-wa feeling in my head, almost like I m going to faint. I feel at once like my stomach is very empty, but then I am naseous. My entire body shakes, even my voice if I try to talk. Sometimes, this is accompanied by a hot flash but not always. I am post-menopausal, have not had a period since I was 50, and had very few menopause symptoms, very few hot flashes. I ve thought this may be low blood sugar, because sometimes, but not always, it helps to eat something. I ve been having these spells for years, infrequently, but in the last year, they have become a lot more frequent, sometimes several times a week.