I was 18 and wrecked my while merging into the highway, causing the airbag to be deployed. We lived in the country, and I got out, walked up the ramp and to the Burger King I worked at. One of my friends gave me a ride home, and I waited for my parents to get home before returning to the scene and getting the car towed. No police or medical were involved afterwards. Now, fast forward a couple weeks...
One day I started getting some discomfort in my chest, but I figured whatever it was I would "tough it out" and it would pass. After a couple of days it swelled to almost a b-cup size, and I couldn't take it anymore and told my parents. My mom took me to the ER and they rushed me to a room, and hooked me to an IV. They started asking questions, trying to determine the cause, and I guess the head nurse wasn't happy with the cause being blunt impact to the chest from the airbag, and told my mom to leave the room.
From there she went into "Ok, your mom isn't in here, what really happened?", and when I said I didn't know? She said "Oh come, you didn't try to pierce yourself? "You didn't inject drugs in there?", "This isn't an injury from some kind of sex act?"..no no no. I ended up having a wick put in, and having to get it cut and drained three more times over the next few weeks..but they never got the answer they were looking for.