The result of fucking so much and to the point that one is physically and mentally exhausted from the process that they need an ample amount of sleep to regain energy and thus being able to perform daily tasks, along with more fucking. It is similar to being jet-lagged, but from fucking too much.
Blake: Dude, Ashley and I fucked for 8 hours last night, I'm exhausted.
Pierce: You must have a seriously bad case of fucklag.
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.