I also have what you desribe, the permanent changes due to some noise exposure. Trouble is I'm now getting changes for the worse when I havent been exposed to noise. I'm so scared, nay terrified. I know that wont be helping but I just am. My legs turned to jelly today now that its become clear I have it in both ears as a nasty electrical noise.
Yours was only a small event though, not like an hour of organ music. It was just a few seconds. So this may then be a temporary spike. Hope so. The only thing you actually can do is try to forget it, there actually isnt anything else for us to do is there?