Have Tiredness While Waking Up And Struggle To Get To Work. Fatigue Disorder?

Hello, I m Yvonne. I have been sick for about three years, and 4 to 5 days a week. I wake up tired and my Dr. has me out of work right now, my return date is in one month (4/5/2013). I struggled to get to work a lot, informed my Dr.s , anyway, it hit me the other day like a landslide. I really forced myself to get things done and made a appointment to see my Dr. I lost 20lbs the last 12 months. I believe i have fatigue disorder? Your input will give me some insights,thanks Yvonne