what would they do if you spermed into a drug test
You mean came into the drug test, right? Using 'sperm' as a verb...genius.
They wouldn't DO anything. Unless its all semen and no pee. They'd just think you're one weird dude. By the way, when you take a drug test, make sure you spill some piss over the side of the cup and hand it to your parole officer if he's a douchebag.
Don't worry, they are so dumb they don't even know the difference :D
It wouldn't invalidate the test, if that's what you are looking for.