@Kells You might find that the sound settles a bit, it does happen. You also have no way of telling if it's loud in the beginning because you're monitoring and do not have perspective on it. It will sound loud to begin with.
I'd love to press the fast forward button for you. It is a real struggle in the begging.
Your old life is not dead, parts of it might be different if the tinnitus sticks around. You'll get used to a new reality (I can still feel my anger at having to get used to a new reality as my therapist called it at the time). But it will become your new normal. The fear will gradually subside.
It is thought TMJ can cause tinnitus - Dr. Susan Shore is carrying out a trial on treatment for somatic patients at the moment.
Your ENT should know about the possible correlation; 1 out of the 3 ENTs I saw also told me there was no correlation with my jaw and it was purely neurological.
I've had TMJ since my twenties and also developed tinnitus (with no hearing loss) out of the blue. Having said that I also had a noise exposure the day I got tinnitus (albeit not a hugely remarkable one) which meant I dismissed the jaw cause for ages. Now I think TMJ had a part to play and should have gone back to the splint sooner. I didn't for various reasons...
As I said in the beginning you are so early into this journey and if after a couple of weeks you have managed to tune it out for part of the day, that's pretty good going...
You'll have more and more of those times. We're so used to going to doctors and getting fixed or treatment options that having nothing feels so depressing. Their dismissive attitude to tinnitus is not uncommon I'm afraid.
Keep busy and engaged even if you don't feel like it.
Stay strong, this is the hardest part.