Looking for tinnitus advice re. sudden sounds and pressure changes

Hi all, first time here and hoping for some advice and that someone has a similar experience to me! I'm 36 and have had tinnitus for years. I say that, but I only realised I had it in the past few years – before that I honestly though that the high pitched noise was the sound of silence! It was only when trying to explain this to my partner when walking in Dartmoor that I finally realised that not everyone heard what I heard! My dad has tinnitus so when it clicked I wasn't too concerned about it - some days (particularly nights) its louder than others, but in general it's not THAT loud (though I have learnt the hard way to wear ear plugs to gigs) and I am quite used to it.

Particular things are concerning me though. Sometimes, often in the office or when walking underground to the tube, I will get a sudden 'noise'. It kind of feels like there has been a really sudden change of pressure - such a surprise it kind of takes my breath away - and then it drifts off again, so lasting maybe 5 seconds. Other times it's just a sudden high pitched noise, again for a few seconds. It does change, but it's hard to describe as it's so sudden and short-lived. I do distinctly remember one time when I was walking down the stairs on the underground, and just out of nowhere it felt/sounded like my head had just been dunked under water - a swoosh sound, a change in pressure. It was really weird and disorientating - I almost fell down the stairs. Often when it happens it's so loud/uncomfortable/surprising that my instant reaction is to cover my ears, which is a bit embarrassing in public, especially when it dawns on me that no one else heard/felt it but me. This isn't a frequent thing, perhaps a few times a year? Though sometimes clustered within a few weeks. I really should be recording it I know but never remember.  . 

I  did go tot a GP and told him some of this. He asked me if it was in one ear or both... I honestly hadn't thought about where the sound was before, it was just something that was there, so I said both ears. He said that that was less of a concern which was reassuring, but then of course I started paying attention, and actually it is on the left side. So now I'm a bit more worried about it!

The GP did say that if I wanted he would refer me to a neurologist, but I said no at the time. Now I'm not so sure... but I also know I can be a bit of a hypochondriac and an over-thinker so thought I'd see if anyone had experienced similar and had any advice! And also if I should see someone to get it checked out, would it be an ENT or a neurologist? 

Thanks for reading,