When you say you have been eating this way for "a while" what exactly does that mean? Have you been eating a clean paleo/primal diet for years/months or days? I can see those symtoms happening when you are still experiencing the carb flu but it normally stabilizes after a few weeks to months. Also, when you start eating less processed junk you will be getting so much less sodium in your diet. Low sodium can lead to a lower blood pressure and Orthostatic Hypotension especially if you are sitting for long periods of time. Orthostatic Hypotension can cause headaches, nausea and dizziness when getting up. I have had it happen to me before on a number of occassions and I have been pretty strict paleo for over 5 years. Since I went paleo my BP wont go over 100/65 but sometimes it will measure in the 90/60.
Orthostatic hypotension - Wikipedia, the free encyclopedia
"If man made it, don't eat it" - Jack Lallane
People say I am on a "crazy" diet. What is so crazy about eating veggies, fruits, seafood and organ meats? Just because I don't eat whole wheat and processed food doesn't make my diet "crazy". Maybe everyone else with a SAD are the "crazy" ones for putting that junk in their system.