Fainting while pregnant

Anyone else faint a lot during pregnancy. With my first born I never had morning sickness and I passed out like 3 times during that pregnancy. Each time was after I was 20+ weeks I think I was 20 weeks the first time then again after the glucose test that time was bad because I hadn’t eaten my grandma said I fainted and had a seizure in the car otw home. I woke up to fire fighters tossing me around. And again when I was like 36 weeks or so. Each time it was hot outside I had my son in August so it’s no wonder my bp fluctuated so much that pregnancy. This time tho I’m only 7 weeks (today) and I had had morning sickness from like 5 weeks but no vomiting only nausea until like the 8th I couldn’t eat anything I couldn’t even drink water or pedialyte without throwing up. I contemplated going to the ER at 5am because I had been up all night throwing up hoping to just get some iv fluids and maybe I’d feel a little better but the er was packed and we weren’t top priority so we left. I went to urgent care and they gave me promethazine for nausea. That worked and I ate something and thought that I was ok to go into work… I go into work at 11:30 and didn’t even last until noon. I’m so embarrassed that happened at work and I feel bad I couldn’t stay to help out. But my drs can’t give me a good reason at all to why. I know it’s probably because I was dehydrated I had eaten and drank pedialyte and managed to keep it down but I probably should have just stayed home.