Im from Louisiana! I feel your pain with this weather. I still have my air mostly freezing everyone else out.
I haven't had bad morning sickness, but I have had some of the sensations you're describing. I live in the south so our weather is still in the fifties and sixties, but even when I wear a light jacket I feel stuffy, hot, and like I can't get enough air. It's at its worst in the car! Luckily as soon as I get the jacket off and cool down with lots of air, I feel better. Best of luck to you! I know it's worrisome.