Eggbound Hen?

[FreeChicken!]

Today my three-year-old White Leghorn hen, Lily, sat in her nest almost all day, only getting up when another hen chased her off. I let all the chickens out of the pen, and she mostly just sat next to the fence and dozed off. She looks tired, though I can't be sure since she usually looks tired due to one droopy eyelid that she's had almost all her life. Her appetite is normal, however, and she was quite eager to eat her supper. She hasn't laid an egg yet today, just sat on the nest.
Is it possible that she's eggbound?

 

[FreeChicken!]

No ideas?

 

[Tongiechick]

she may just be broody

 

[FreeChicken!]

Leghorns don't get broody though, right?

 

[A Chicken Owner]

Leghorns rarely go broody but it still is a possibility