Sorry to be the bearer of bad news but you may well have permanent tinnitus. It can happen from a single exposure to very loud noise. I hope you have escaped it but if it is not gone in a few days the odds are very poor.
I have had it now for seven years. I got mine after a some ear problems but the key even was my own voice. I was in the habit of singing extremely high pitched screams with metal-ish music and didn't heed the early warnings.
Doctors can't really do much. Miracle "cures" are offered on the Internet but don't waste your money. While some ideas can help some cases, those who have it from exposure to noise are usually stuck with it.
Whatever you do don't get obsessed by it because that is the worst thing. You need to learn how to ignore it. There are people who can help you with psychological techniques. Mostly it involves masking and distraction.
I have better and worse times over days months and years. The biggest problem I find is that it can inhibit sleep and being tired makes it worse so it can get into a downward spiral.
If I was in your situation I would consider reporting the pub for exposing patrons to dangerous sound levels. If someone successfully sued a venue so much damage could be avoided. However that would be a good way to get obsessed about your tinnitus which would work against managing it.