Thanks for the response - I find it helpful to give my honest experience to others on this forum that things can and will improve given plenty of time - even if I do suffer from rather non-standard tinnitus issues.
I have had times where it starts to scream so loudly that I don't sleep at all (and without an apparent trigger, either). In the past, this has been for weeks on end, rather than 1 or 2 nights. Fortunately this hasn't been the case much recently, with just the odd, bad night. It really is difficult to know what to do as I have tried to eliminate/overeat possible triggers and it makes no difference either way!
Weird thing is, I occasionally suffer migraines (loss of vision, weird colour distortion etc.), but this has been the case since I was about 10 years old and has never got better or worse and since it affects less than 1% of my life, I'm really not bothered by it. Anyway, the point is that with migraines, you get an aura before one, a weird sense that it is starting long before you really have any tangible symptoms. I get the same thing with tinnitus. I can sense a few hours before it gets bad that it is going to be bad. Not because it gets louder, or I have exposed myself to anything loud, it's a sensation, rather than a sound.
I'm half expecting to be sectioned next time I see the eNT...
I hope yours settles down again soon.