Alone in a dark room: How did you get there?

I find myself here in this dark room because I am tired. I am laying on my stomach, relaxing on my bed just thinking about the day I have just had. My sister left for California today and I also moved more things into my apartment. I have been out in the living room with my roommates, hanging out, and playing some card games but I found myself getting very tired. So, I decided to come in here. Today was a very long and sad day in more ways than one. As I lay here I am contemplating how this year without my sister and living in an apartment with 3 other girls will go, and I am also wondering how my first classes of the semester will go over tomorrow. The dark is a good place to clear your mind, you're free from noise, from light, and from others. I find myself thinking a lot of my sister leaving for California, and all the recent changes in my life, and about school starting up again. I guess, I find myself here because I need to think and clear my mind of all the things clouding it. When I find myself overwhelmed I like to just think the situation over and figure out a way to go about dealing with something or completing homework or a certain thing I need to get done. The dark, especially when laying in bed before sleeping is my way of going over my days; What I've done; What I need to complete; and sometimes I think of things I should change.