Hi,
@Bolomom, and welcome to Tinnitus Talk!
I'm sorry you're having difficulties with your recent-onset tinnitus. It is always hard to say what may have caused your tinnitus, but the main thing now is to find ways to cope with it. Tinnitus is always worse at the onset, and for many of us, it seems to calm down over time. I know it has for me, and for many others on this forum.
I've had several tests, too, and nothing was found (MRI/MRA with contrast, and CT scan). I have a ringing/hissing sound, and I also have pulsatile tinnitus (heartbeat sound in ear). I'm glad to hear that the results of your CAT scan were negative, and the fact that you're in excellent health is a good sign that you're doing things right. At the onset, it might be good to watch your diet and note if any particular foods or drinks cause your tinnitus to spike (such as caffeine, sugar, etc.) Don't give up on exercise, or on doing the things you love to do. If you can stay active and busy, you will be more likely to habituate to the tinnitus, and put it out of your current thoughts (easier said than done at the outset, I know!!).
Are you going to continue taking the anti-depressant? Since that doesn't seem to be the cause, it might be good for you to continue taking it, so you will remain calm and relaxed. Are you having any sleep problems? Also, have you been tested by an audiologist for hearing loss?
Look around on this forum; there is lots of great information here, and many good people who will help and support you on your journey.
Best wishes and support,
Karen