Selena Gomez is under the weather.

The singer and actress, 18, was rushed to an L.A. hospital Thursday night.

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Her rep told Us Weekly on Friday: "Last night after Selena's appearance on The Tonight Show she wasn't feeling well and was taken to the hospital. She is currently undergoing routine tests."

TMZ reports that the Wizards of Waverly Place star (and girlfriend to Justin Bieber) was complaining of nausea and an extreme headache after her TV appearance.

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During her pre-hospital chat with Jay Leno, Gomez revealed that her mother Mandy approves of her daughter's world-famous beau. "[Bieber] passed the test," said the Monte Carlo star, who got acquainted with Bieber's own brood over Memorial Day weekend.

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