Britney On the set of "Piece Of Me"

Balancing mommy duty and her music career – it's all in day's work for Britney Spears.

After spending Tuesday with her two sons Preston, 2, and Jayden James, 1, Spears switched into pop-star mode, arriving at L.A. restaurant and nightclub Social Hollywood to shoot the video for her tabloid-bashing single "Piece of Me" – the second single off her album Blackout. (It's being directed by Wayne Isham, who helmed Spears's "I'm Not a Girl, Not Yet a Woman" video.)

Spears and her backup dancers donned identical blonde bob wigs and black trench coats. The premise? "The paparazzi are following [Britney], so they're dressed alike to trick them," a source close to Spears tells PEOPLE. "They all go into a club to get away. One [photographer] sneaks in, but Britney, in the end, discovers him."

The stakes are high for Spears, whose video for "Gimme More" was poorly received when it was released in October. (The song itself, however, was a hit.) "[Spears] is really freaked out about everything," said the source. "She's just really nervous and feels like everyone might make fun of her again."

Lets just hope this is a good video. Not like gimme more. Piece of me is a good song so i just hope she takes time out to promote them!

Which ones Britney?