Didn't see the show... but did she drop her mic at the end of the performance? Then she did literally drop her mic. If she made a statement and ended with a bang but did not drop her mic then it's s figurative mic drop.  Literal means the thing described is happening. If I say he literally kicked butt, that means his foot made contact with the butt of someone. Usually said in front of an expression that has a common figurative meaning. Like kitness was literally on fire in her performance before the hunger games.