Don't mess with Selena Gomez.

During an appearance on the "Late Show with David Letterman" Monday night, the actress admitted she made ex-boyfriend Justin Bieber cry.

"The last time he was on, he and I got into a conversation and he said something and then I said something and then he said something and then I said something and I made him cry," host Letterman said.

Gomez burst out laughing before quipping, "Well then that makes two of us."

The 20-year-old also revealed that she's doing "so good" and is happily single but not dating yet.

The pair split last November blaming busy schedules and long periods away from one another. Shortly after their break up, Bieber told Billboard magazine, "I'm not in the happiest place that I've ever been. I'm trying to get through what I'm going through….[but] I have my really close friends to cheer me up and keep me going."

Gomez is currently promoting her new film "Spring Breakers" in which she stars alongside Vanessa Hudgens.

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