Silver water Bottle, hidden Threat, and the waiting Room

"I was looking for my silver water bottle under the passenger seat of an old minivan I don't own, parked in a dim concrete garage that smelled like exhaust and wet asphalt. I couldn't find it, so I stood up and closed the heavy sliding door, which made a loud metal latching sound that echoed through the empty floor. A guy in a dark hoodie standing by the concrete pillar about twenty feet away raised his arm and there was a quick, dull pop--almost like a thick plastic bottle collapsing under someone's boot. I felt this hard, heavy thump right in the center of my ribs, like someone had thrown a brick at my chest from a couple feet away. It didn't burn or hurt at first, it just knocked the breath right out of me, and when I reached down to feel my shirt, the cotton felt thick and warm against my knuckles. I was mostly just baffled why he'd do that when I didn't even have my wallet on me, just a handful of loose receipts. Then I was suddenly lying on a red vinyl sofa in a doctor's waiting room, staring at a framed poster of a lighthouse on a cliff. The room was totally quiet except for a fluorescent light buzzing overhead. My shirt was still damp around my stomach, but I wasn't bleeding anymore, and I kept trying to use a ballpoint pen to poke a hole in a magazine cover while I waited for someone to call my name. Woke up taking a ragged breath, pressing my hand against my ribs to make sure nothing was sore."