If you're not having medical problems-consider exercise. It sounds crazy, but you have to use energy to have it.
Over 10 years ago I was exhausted for what seemed like six months. I finally went in and my iron was way low. It didn't even take a supplement-I ate iron rich foods and after a week and a half, I started to feel so much better. Now I know what my symptoms are and I just have to up my spinach and blueberry smoothies for a few weeks.
I do recommend seeing a doctor. There are just so many things that it could be.
Congratulations on being clean, that is amazing!