Did your doc check your blood pressure? I had this and she did and it was a bit low, not dangerous, but low enough to make my dizzy and sometimes black out.
You can run down to a local pharmacy if they have a machine and check yourself.
My doctor told me to make sure to eat frequently- small meals or snacks like every 2 hours. The idea is to eat BEFORE you get hungry- which often means forcing it down but it's better than the dizzy spells. Healthy snacks. A fat/protein/sugar combo is great to keep your bloods good. Like and apple and almonds. Of course a lot of water too, like the previous poster said, stay well hydrated.