I don't know if I'm actually dropping into ketosis, but I get all those "good" ketosis smells if I hang out at 100g of carbs a day, and I'll drop into it overnight.
It's entirely possible to get "carb flu" on day one, especially if you've had a high sugar diet. That will do crazy things for your blood glucose.
I didn't like the rules you gave me, so I made some of my own.
Strong people are harder to kill than weak people, and more useful in general. - Mark Rippetoe
Welcome! I too, am a newbie to the Primal lifestyle and came from a diet of the conventional wisdom of grains and processed easy foods. I started Primal on 16 January, and went cold turkey from all my old vices of sweets and sodas on the same day. UGH. The first four days I had headaches and generally felt blah. HOWEVER. By day 10, I've noticed that when I wake up in the mornings, I am totally awake, not sluggish like I used to be. My general energy level seems constant throughout the day and no more headaches at all. Sounds to me like your body is just adjusting to not getting all the natural sugars it was before you switched. I'm new, but that seems like common sense. (At least your body was used to natural sugar, mine was used to Little Debbie cakes and Soda)
Advice for you from a 25 year coach? - Don't quit after just a few days. Something like this is a lifestyle change. It will take time to fully realize it's potential. Learn all you can, and make changes as you learn.