How do you think I should decorate my room?

How about red walls... You can accent with some great comforters and pillows that you could find in your taste. Also, maybe some throw rugs that match...maybe in some design with black and red. I have stapled fabric on my daughters ceiling because she wanted it painted black, and I thought it would be too hard to cover up later, so I billowed the fabric in sections and stapled it up. We found this black velvet fabric that looks great. Her walls are hot pink...but, I think it would look good with red, too. If you have windows, maybe some black curtains that have a tie back if you want to let in some light. Hope this helps