Ya, check with the doctor to see if there is hearing loss by the xbox. Even if there is, it is not the end of the world. You are so young, you can adjust and adapt. My specialist MD told me that he had T from 13 and he lived fine and went on to medical school. So just relax and keep calm.
For the time being, you can do some masking to help you relieve your anxiety. There should be many free apps now for sound generation or sound synthesis for you to find some tracks which can mask your ringing. I used masking heavily during my early days. A CD player by the bed helped me sleep. An ipod loaded with nature sounds was always in my pocket so I could get masking going with mobility. At the office, my work PC was loaded with 'aire freshener', a free sound generator. When you know you don't have to face the ringing head on, it can calm the nerve. Of course, as time goes by, as you get more used to the ringing or as the ringing becomes less loud, you can cut back on masking. Best of luck and don't worry too much.