You may just be going through detox. I had most of your symptoms for the first 4-5 days of induction-- I also had a low grade headache that lasted for 6 days. Damn carb withdrawal.

Anyhoo, give it a few more days and you should see major improvements. The only way you wouldn't feel any better is if you actually do have a cold of some sort.

Hang in there and keep up the good work!
Nikki