Passing out?

I’m 21 weeks and today was the first day at my new part time job being a cashier for a family friends restaurant. Well my shift started at 10am and by 10:45 I had passed out. And I mean cold, on the floor, out. I told my manager I was fine, I drank some water and ate something sugary. By 11:15 I was dizzy again by caught myself in time. By 11:30 the same thing happened and by 12 I was on the bathroom floor in cold sweats trying to stay conscious. Luckily since it’s a family friends restaurant she sent me home to try and get better for my shift tomorrow. This has never happened to me and it was very scary. I ate before I went into work and no I’m not hydrated like I should be and my doctors know this. Has anyone else had this? The just random passing out? Especially this much in a day?