Do you think feeling sleepy is an emotion caused by my thoughts or a physical sensation?

I feel like its more of a physical sensation in my body but I sleep so many hours and I feel like sometimes I also buffer with sleep instead of working.

I feel tired, and have physical pain and headaches even though I have slept more than 9-10 hours.

What can I do about this? I want to feel more energized and fresh and active during my day time so I can do my work.