03/10/2009 AT 08:15 AM EDT
Move over Isla Fisher, Britney has her own confessions of a shopaholic!
After performing in Tampa and Miami over the weekend, Britney Spears
retreated to the Mandarin Oriental hotel on Brickell Key Sunday and promptly hit the strip for some retail therapy.
"I couldn't believe I saw her at the mall," a staffer at the Bluemarine store at Merrick Park Mall in Coral Gables tells PEOPLE. "I ran over to her while she was at The Grape and gave her my card. I was so excited I was sweating. I asked her to shop with me the next time she is here. She was so sweet and southern."
After Spears, 27, had a salad for lunch Monday with a girlfriend-assistant and two bodyguards, the entourage walked around the tony Spanish Mediterranean-styled mall, stopping at various stores, including Nordstrom, Neiman Marcus, D' Nature and Jimmy Choo.
"Britney looked so fresh and was so nice," a source at the high-end shoe store tells PEOPLE. "She bought shoes, sunglasses and bags and thoroughly enjoyed the shopping experience."
Another mall retailer confirms: "Britney looked really relaxed and happy."
Later that afternoon, Spears took her boys – Preston and Jayden – for a swim in Mandarin Oriental pool.
Wednesday night, the star resumes her Circus tour up north – performing at Nassau Coliseum in New York before doing two nights in Newark, N.J.
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