Have any of you experienced anything like this during your pregnancies?? If so, do you know what caused it or did it just pass?

I keep getting severely lightheaded and dizzy, seeing white spots, my legs and arms get super shaky. This isn't just dizziness when I stand up too fast. Most of the time it starts in the shower and lasts for a good 30 min. My blood pressure has been fine during my doctor appointments and I've never had an issue with blood sugar.