Lindsay's in No Mood to Party

The actress gets cranky at a Hollywood party. Has La Lohan had enough of the scene?

Lindsay Lohan brought the drama at a BlackBerry party Thursday night at Il Cielo in Beverly Hills.

Sources say that shortly after girlfriend Samantha Ronson started spinning at 11 p.m., a scowling Lindsay showed up and headed straight for the DJ booth.

"There were a bunch of girls crowding around the booth, and Lindsay pushed them and flipped the group the finger," a partygoer tells E! News. "Her bodyguard was apologizing to people, saying she just gets tired of people taking her picture."

"This is not true," says Lohan's rep, Leslie Sloane Zelnik, of the alleged bad behavior.

However, the source says that after spending a few minutes with Samantha while she spinned, Lindsay settled in at a VIP table with friends—and her mood didn't seem to improve...

"She just sat there texting and flashing angry looks at Samantha," says the eyewitness. "I don't know if she was jealous or just in a bad mood."

At one point, Joe Francis, with whom Sam and Lindsay are feuding, came up to Lindsay—but she ignored him and he quickly left.

But seems LiLo wasn't the only party pooper. The event was shut down at 12:30, making for a relatively early evening for Hollywood's late-night crowd.