Doesn't mean you are fat-adapted, but you confirm why I don't recommend going very low carb. People that are VLC generally experience that when they do have a decent amount of carbs. If you have some carbs everyday, you can maintain your flex fuel system much better by being able to handle both sources of energy.
I really regret it when i even eat a little bit of grains, not as bad with sugar, but grains do me in. insulin resistance is best determined by taking blood glucose readings at different parts of the day. Insulin resistance depends on your health history and how you are taking care of your body now, it's not easily revealed without more information.