Celebrities: They're just like us! Even the most famous pop stars catch the flu bug every now and then — at least, that's what seems to have been ailing Rihanna recently.

The 24-year-old singer issued a colorful complaint about feeling under the weather via Twitter over the weekend, and then surprised her 18 million followers with the photographic proof of her unidentified illness Tuesday with a Twit pic that showed RiRi in bed with an IV in her arm.

According to People, a source close to Rihanna said the singer is on the mend and was not suffering from anything serious: "She had a fever and flu since last week and needed an IV, but is fine now."

Not that we're qualified to offer a diagnosis here at MTV News, but judging from all the traveling, performing and promotion Rihanna has been involved in during the past month leading up to the release of her first movie, "Battleship," as well as her performance on "SNL," it seems likely the young woman was simply worn out. Here's hoping she takes some actual time off for rest and relaxation.

Meanwhile, we only have to wait a little while longer to see the "Where Have U Been" singer in her big-screen debut, a role that Rihanna said she relished because she got to be a total badass.

"I wanted to do something badass, but I didn't imagine it would be grungy, like straight Navy soldier, no makeup," Rihanna said of her expectations for her first movie role. "I enjoyed it.

"Battleship" opens May 18.

Check out everything we've got on "Battleship."

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