When I was in the nausea faze I would always gry sick when I was hot never failed ! Shower, working out, cooking. Maybe try I colder shower !
I use to take hot baths and showers. But when I was hospitalized my last pregnancy I was informed that those bring on labor.
I take really hot baths and what seems to help is leaving the door open so the cold air can come in. :)
^ I agree with using cooler water.. I felt like that my 1st pregnancy. Real dizzy and sick and that worked. Also, try to eat something before you get in the shower.
Try turning your water a little colder. I used to love warm/hot showers and now I almost pass out. So I usually turn it to where its slightly warm slightly chilly. Makes me feel 10times better.