Val, how good that you get some relief with your hearing aid, I wish I had your luck. Unfortunately, I can't use hearing aids like you do because my tinnitus badly reacts to noise, even to my own voice if I speak too loud. Go figure, I'm almost deaf and hearing aids are banned to me. Ironies of life.
It's a bit strange though that the tinnitus didn't show up before the abscess, if it's indeed related to your hearing lose. I still think (and wish) that your tinnitus will diminish little by little.
About myself, I already had a serious hearing lose in both ears (meanly in left one) before my first tinnitus on set, which is antibiotic (Metronidazole) induced, and never before it I had experienced any sort of tinnitus. Hearing lose doesn't always mean Tinnitus, generally, there is a cause that triggers it. In my case was ototoxicity, latter on aggravated by an anaesthetic with ototoxic potential again which I was not aware of. In your case it might be a lot of stress related to the infection, who knows, but certainly nothing to worry about in your brain, surely not. Your scan will be fine.
I'm now looking for a different solution because I was supposed to have otosclerosis, wich I apparently haven't, so things might change a lot for me. You know, I was diagnosed with this problem by different doctors (reputated ones) in the last 30 years, just to find out last moth, by a high resolution scan, that my middle ear bones are absolutely non otoesclerotics, they are fine. I now know it was a clever decision I took when I refused all those stapedectomies that I was offered by the myriad of doctors that saw me in the past. Side effects can be horrible if the stapedectomy surgery fails, and it can fail as any other medical procedure do. At the moment I'm after a Baha implant for the middle ear, but, for this to be possible, my inner ear should be fine, otherwise that kind of implant won't be available for me. I've an appointment with an otologist team who will check if the implant in my case is going to be a valid option or not, but this won't be till February (Spanish Health System at its best, but, for our shame, it's more or less the same in the rest of EU countries). That will be a long wait for my desgrace, but to pay all the procedure from my pocket is too expensive and I'm a retired person, so it's my only chance if I want the implant.
I wish you all the luck in the world for your tinnitus to settle soon.
Warm regards.