Good evening.
Well, it sounds like your imagination is going to be your best tool here. You could begin off with how your person got in the room to begin with. Next you will just have to imagine what their feelings are. What kind of person are they? Are they brave and heroic, or frightened and cowardly? Do they know how they got in the room, or not? Are they able to figure a way out, or not?
Begin by setting a timer for 10 minutes, and spend this time brainstorming what kind of person your character is, and what kind of situation got them into this room. Write down anything that comes to mind. Next, set the timer for 10 more minutes and brainstorm how this type of person would feel under these circumstances; again, writing down anything that comes to mind. Since your essay sounds like it is supposed to spend most of its time describing how the person feels, you might end up spending more time on this section.
Once you've got your brainstorming finished, you can begin to piece the story together. Don't worry about spelling, grammar, and punctuation until way later; focus first on developing your character and explaining how they are feeling.
Good luck!
Regards,
Gloria
Moderator, EssayForum.com
Gloria, EssayForum.com