I have bad tinnitus, and once in a while it will drown out all sound and focus on the ringing. During this time, sound turns into this thing that lives at the back of my head, as if I put my fingers into my ears, like I’m interpreting the sound through vibrations or something. I can’t really explain it, but it’s a “different way” of hearing. Sounds a lot like what you’re experiencing.

PS: Don’t blast Tool albums for two decades strait into your ears.