Help!😩

Okay so mommies..I'm 27w4d with my first. Here in the past 5 weeks I've been getting super dizzy like I'll get sick and then everything starts to go dark. Usually sitting down makes it stop but here lately it happens sitting down and standing up..I've told my dr and all he said was its normal but i just don't feel like it is..the last few Dr appointments my bottom number on my blood pressure has been kind of high..not to high just a little more high than normal the dr doesn't seem concerned but I am...I'm not sure if it has to do with my blood pressure or what? Is anyone going through the same thing or has gone through the same thing?