Britney spends a girls' night out

The singer went out on the town with two female pals for a long round of dinner and dancing.

First stop for Spears and her friends, Alli and Jessica: Dominick's in West Hollywood, for a healthy meal of grilled rare Hawaiian blue fin tuna with lemon pesto and sugar snap peas. According to another diner, "Britney was in really good spirits. She was having a fun girls' night out with her pals."

Then the ladies when off to club Les Deux, where the trio – along with Spears's bodyguard – arrived just after 11 p.m. and commandeered "the playpen," in a secluded area of the hotspot.

"Britney was dancing like crazy and in a great mood," an onlooker tells PEOPLE. "She seemed like she was on top of the world and wanted everyone to see her."

The partying continued, and Spears even hopped into the DJ booth at one point.