People get hurt all the time without noticing it. Occasionally, people get totally destroyed without noticing it, either.
A 27-year-old drunken Frenchman refused to divulge his identity to the police, who responded by shooting him in the head with a Taser (presumably because someone had mislabeled it "Lasso of Truth"). Later on, the man went to the hospital complaining of a terrible headache, as if the troll from Cat's Eye had crawled up his nostril to do Zumba in his cranium.
One of the barbed Taser darts was still embedded in the man's skull and had penetrated his brain, presumably activating a latent invisibility gene because nobody could see this without a fucking X-ray.
A 62-year-old woman was walking to the grocery store when a strange man leaped out and punched her, then ran off without explanation (presumably this was an item on his bucket list). She shrugged it off and continued to the market, because the Cracklin' Oat Bran wasn't going to buy itself.
When she made it back home, her daughter noticed that she had a knife sticking out of her back. The man had actually stabbed her -- she'd walked to the store, made her purchases and walked back home with a blade sticking conspicuously out like a boner in math class and nobody had said a word.
For years, Li Fuyan suffered from constant headaches and shortness of breath, while everyone around him suffered from the hot corpse-farts that boiled out of his open mouth.
When he finally went to the hospital for an X-ray, they discovered a 4-inch blade that had broken off at the hilt in his lower jaw during a robbery attempt four years earlier. This had somehow slipped his mind.
The knife was perfectly wedged just behind his throat, barely missing his carotid artery. He was a violent sneeze away from his face giving birth to a QVC demonstration.
Twenty-two-year-old Paul Edwards and 66-year-old Paul Holloway shared an apartment in Florida. Edwards decided he wanted a new roommate, but still wanted to collect Holloway's Social Security checks, so he shot the older man in the head while he slept.
Holloway woke up, wrote his skullache off as a stroke (as one does), and went back to sleep. The next day, he got into a car accident while driving to a place that didn't exist, probably because he had a bullet lodged in his brain. The EMTs noticed the hole in his head and whisked him to the hospital, and Edwards was arrested for side-splitting ineptitude.
Seriously, man. He was old and literally surrounded by smother pillows.
A Japanese man was out riding his motorcycle with some buddies when he lost control in a curve and bumped into a safety barrier. He steadied himself and rode on unabated, restarting Kenny Loggins' "Danger Zone" on his iPod, until he came to a stoplight a few miles later and saw his friend zoom up next to him clutching a man's leg. It was his leg, which he'd left in the road back by the barrier like an empty Cheetos bag.
Similarly, a man in France was riding his moped when he was hit by a car, probably on purpose. He staggered away from the crash and walked home, eventually hitchhiking the last few miles. Later, when his mom helped him out of his jacket, she noticed that his left arm was gone, which was puzzling, since she was fairly certain it had been there that morning.
Neither he nor the person who'd given him a ride had noticed.
"Are you sure it's not in your other jacket?"