Britney SpearsBritney Spears reportedly had an argument with estranged husband Kevin Federline between arriving home from her brief skint in rehab last week and shaving her head on Friday night.

According to OK magazine, Kevin was at Britney’s Malibu home with their sons, Sean and Jayden, when Britney arrived home and the two had a fight over Britney’s partying lifestyle.

A source told the magazine: “They had a huge argument. Kevin threatened Britney that he was going to have people test her hair to find out exactly what she’s been up to. She was so scared. That was what made her have her head shaved.”

Sources close to the star have said that she has taken ecstasy, cocaine and powerful anti-anxiety prescription drugs in the past.

Another source told People magazine that Kevin ditched his plans to go to Las Vegas for the NBA All-Star game (and parties) over the weekend to stay in Los Angeles with Britney and their boys: “Kevin is concerned for Britney and his children. Of course he’s concerned about her. He loves her. He’s always loved her - even after she started divorce proceedings.”

However, Britney had other ideas and tried to check herself into the Mondrian Hotel instead. An onlooker revealed that she turned up at the hotel in an electric blue wig: “She tried to book a room but she didn’t have any money or a credit card, just a piece of paper carrying a partial credit card number.”

“She kept saying: ‘Nobody wants me anymore’.”

She was later seen trying to hire a rental car but again was turned away: “The staff were stunned and didn’t know what to do with her.”

Britney checked herself into the Promises Treatment Center in Malibu yesterday morning, reportedly at the urging of her father, Jamie Spears. The two dined together on Sunday night and a source revealed: “Jamie just told Britney how much he loves her and that he wants her to get help. He told her that he’s afraid for her safety and that she needs to take a look at her life and make some major changes.”

According to WENN, Jamie was with Britney when she checked into Promises. The center’s treatment usually involves an immediate detox with 24-hour supervision followed by therapy for, on average, 45 days.

However, Entertainment Tonight is reporting that Britney has repeated last week’s 24 hour stint in Crossroads Center in Antigua by checking out of Promises again this morning.