<human>: So I've been sick for the past few weeks with some kind of sinus thing, that dripped into my lungs, thus giving my this nasty cough. I was leaving a class earlier and had to cough, but I figured my cold had to be clearing up, so I didn't bother coughing into the inside of my elbow. Big mistake - I coughed and about a teaspoon of my phlegm flew out and landed on the back of the guy in front of me, all over his windbreaker. He didn't notice, and luckily the two of us were the only ones around for about a dozen feet an any direction, so nobody noticed. I power-walked ahead of him by like 20 feet before thinking about how fucked up that was, seriously I feel like an asshole.

Can you provide a brief rundown of the text in within 3 sentences?
<bot>: Coughed without covering my mouth, slung about a small handful of salty slimy lung butter on some guy's back