1. When a person overreacts to a trifling insult or barb, or to a
joke.
2. When someone acts in an anal-retentive manner, and makes a
big fuss out of a relatively minor problem.
1.
Don't get you're panties all in a bunch, he doesn't mean it.
2. It's not that big of a problem,
don't get your panties all in a bunch, it's going to be okay.