Light headed

Lately I've been getting really lightheaded and its not when I just get up its when I've been up on my feet for a few mins doing my job which I'm an aide and I work in a home with a couple its not my blood pressure I usually have low blood pressure around 80/50 or sometimes lower have had this issues for awhile since I've been pregnant my blood pressure has been 100/60 or alil higher what could be causing this I don't see the Dr for another almost 2 weeks