Hello, I'm Extremely Exhausted All The Time. I'll Sleep 12

Hello, I'm extremely exhausted all the time. I'll sleep 12 hours every night and sometimes take naps and still be tired. I feel nauseous as well randomly throughout the day, and to certain smells, I'm always hungry, and am going to the bathroom more often (urine). I get freezing to the point I need 3 or more layers, and I'm getting extreme head aches. Have any thoughts?