Always Exhauted And Fatigue For No Reason?

No matter how much I sleep even though I get atleast 8-10 hours of sleep I wake uo tired and moody and always have brain fog and head and face pressure,tightness.I been to the doctors and been tested for thyroid,anemia,thyroid,lyme,diabetes had a ct of the brain and nothing abnormal came back.So what could be the cause of these symptoms??