Third trimester and dizzier than ever?

Brionna
Is anyone else dealing with dizziness in their third trimester? I am 28 weeks 3 days. I have been inconsistently dizzy throughout the majority of my pregnancy but the past two weeks have been terrible to the point where I constantly feel as if I'm going to fall over. 
The nurses and doctors have told me drink plenty fluids, eat snacks throughout the day and rest. I have done all of these things and still I am dizzy. 
Anyone experience something similar or have any advice?