I fell asleep last night, while I slept I could see a picture in my head, does anyone know what it means?

When it’s dark outside I can still see things, I’m not sure what it is, but I can see them outside. They never get close to me, and I never want to go see what it is. I know it’s there. I fell asleep and could see a picture in my head, I was running through a field of tall grass. I could see the sky above me. A feild is a good place to find mice. I was running, and i wasn’t thinking of mice, and i wasn’t thinking of girls. I was thinking of me and how wonderful it felt to be running through this feild. I didn’t think of dogs, or crossing the street, or my food bowl. All I could think of was being loosed in the feild, running and jumping. I couldn’t see those things in the dark anymore. I don’t want to eat any mice today.