A bruise, in the shape of a mushroom, obtained by being slapped with a large penis or penis-like object.
"Dude, I can't believe you goin' out with the new girl from accounting!"
"I'm gonna mushroom-bruise her ass, just for you. Just watch -- she won't be sittin' straight for a week."
The act of pulling out your penis while being blown, and systematically slapping your partner's face with it, thus leaving a purplish bruise resembling the tip of you penis (a mushroom).
While our lifespan is the number of years we will live, our healthspan is the number of healthy years we will have and our sexspan is is the number of years we will continue to be healthy enough to continue having an active sex life.
A lighthearted reaction upon receiving disappointing news of some sort. Usually something that isn't a particularly a big deal, esp. when it primarily affects someone else - sort of a mild schadenfreude. Sometimes doubled or tripled, and possibly said in a sing-songy voice for added comedic effect to imitate a muted trumpet, which is how the meme originated.
You didn't get any napkins with your takeout pork fried rice? Womp womp.