Years ago, before news of the benefits of hearing protection reached rural northern Missouri, I went out shooting with my dad one day. We were primarily shooting a .357, and probably put a couple of hundred rounds through it. After that, my ears rang nonstop for months. Eventually it went away, but my hearing was never the same after that, and it's only gotten worse. I don't know if that's tinnitus or not, but I've been told that when your ears ring like that it's basically part of your eardrum dying, and after it stops you'll never hear anything in that particular sound range again.
Now, if I'm in a place with a lot of background noise, like a bar, I basically can't hear anything anybody says unless they're talking right in my ear. People probably think I'm an asshole because I don't talk much when I go out, but I just can't hear them, and long ago tired of leaning across the table yelling "WHAT?" over and over.
Also, I may be an asshole regardless of hearing loss. Opinions vary.
