Courtesy Rihanna; Inset: Evan Agostini/AP
is on the mend after recently being stricken with illness.
"[Expletive] bein sick!" the "We Found Love" singer, 24, Tweeted
on Sunday, followed by a photo
on Tuesday showing an IV in her arm.
There's been no confirmation of reports that the singer was hospitalized, but a source close to the pop star tells PEOPLE: "She had a fever and flu since last week and needed an IV, but is fine now."
And indeed, she does seem just fine.
Since posting the alarming photo, the Twitter-happy starlet has been posting away like usual.
Reporting by Joey Bartolomeo