I got told that it could be indeed the case that my brain continuously has small seizures but only from time to time they break trough and cause the pain and auras which I would then experience. They wanted to measure the brainwaves to figure out if that was the case. That would also somehow fit what OP said, so I guess this is known in the medical world already. Or at least something in that direction.

Well, I think the Auras is my brain failing to filter out visual noise, which then get's into a feedback loop and builds up. And that might be related to other filter functions failing. I think that, becaus4 once in a while, I'm able to suppress the Aura conciously, when it is still very small.