I think it would be an excellent idea for you to write an essay about your room. A French writer named Xavier de Maistre wrote an essay titled "Voyage autour de ma chambre" (A Voyage Around My Room) while confined under house arrest in the eighteenth century. I wish I could tell you more about it, but I have to confess that I liked the idea very much but never got around to reading the work.
You can't write about anything without writing about yourself. There is the object and then there is the subject (you) looking at the object and having thoughts, feelings, and memories about it. You can focus on a single object and have a great deal to say about it if you give it some thought.
A woman once told Henry James that she wanted to write about a certain subject but was afraid it wasn't sufficiently important. He told her: "Write about it and you will make it important."
If your room is important to you, you can make it important to a reader. I am reminded of the term paper Holden Caulfield wrote about his brother's baseball glove in The Catcher in the Rye. You can not only write about your room, but you can stop anywhere while voyaging on a clockwise or counter-wise journey and tell about one particular object. (Are you going to journey clockwise or counter-clockwise?)
For example, I have a wall calendar above my desk which features reproductions of paintings by Claude Monet. I love Monet's Impressionist paintings and could write a great deal about just the one for February, which shows an old sailing ship with storm-tattered sails. I could write about the pictures I haven't seen yet because I only turn the pages once a month, and I could write about my daughter who gave me the calendar for my birthday because I sort of hinted that I like Monet.
I think writing about your room would be a great opportunity, rather than having to write about some assigned topic that could be like pulling teeth.
Best of luck!