But, I've never been able to handle environments with too much stimulus (bars/clubs), when someone's voice is overlapping with a dozen other voices in the room: I can't understand them. When there's constant noises, light displays, many events around me: I feel a sort of confusion / cognitive dissonance.

Doesn't sound like a hearing problem to me. It sounds more like you're easily overwhelmed, which is pretty common, and may mean you have a very very slight amount of sensory integration difficulties, which is one symptom of the autism spectrum.