4 days no carbs and I feel the difference

I am working on a lifestyle change. Each month I have eliminated something from my diet. Starting with no alcohol in December, no fried foods in January and no carbs in February. I have to say on day 3 I feel a change in my body. I'm up late at night, I'm hungrier, I have little energy. The plan is no carbs from Monday -Saturday but I'm not sure I need to eat any! This sacrifice is the hardest but down 4lbs!