There's some kind of supercrud out there. I went from "huh, it kinda aches when I chew" to "I don't have time to bike to the urgent care, I won't be able to stand in about 45 minutes" within about six hours. Got to urgent care, got an intramuscular pain killer, got some oral antibiotics and my eardrum burst of its own accord about 6 hours later.
I also have a uselessly high pain tolerance. I have a scar in my palm where I put a cigarette out in it to see if I could and another on my back where I leaned against a nail in a sauna long enough to get a 2nd degree burn without much discomfort. I also have a grandfather who died of gangrene when the capsaicin cream they put on his leg gave him chemical burns before it restored sensation so I'm not particularly macho about it. And I've had a couple-three ear infections that just rose up out of nowhere.
Not sure where the hell it's from, but there's something nasty that likes eustachian canals.