HELP!!!!! passing out while pregnant

Ke
I started having some sudden dizziness. I didn't think much of it. Last night while cooking dinner I felt it again and then passed out. Was planning on calling the doctor today but before I could I had another spell where I passed out and got super super sick. 
I went In to my doctors office and they basically told me "you're pregnant, that's why". My blood pressure was a little high at the start of the visit and then it plummeted and I felt like I got hit by a bus. 
I don't feel comfortable with the "you're just pregnant" answer. I am 34 weeks with my second and this doesn't feel like "just pregnant." 
Anyone else experience this?