Singer is nervous about her comeback gigs

Britney Spears is apparently battling bouts of anxiety in the lead up to her world tour.

The singer, 27, is thought to be concerned about how well her concerts will be recieved.

Her dad Jamie is even said to have called in doctors to help calm her down.

‘Britney is in danger of not going on tour as she has been having paralysing panic attacks,’ a source tells The Sun.

‘Every time there is a crisis, Britney screams and cries and locks herself in her room.

‘She has been telling her doctor she feels under pressure and ill when she thinks about touring.

‘She is worried about being on the road, and fears that her performance will be branded a flop.’

The Circus tour starts in New Orleans on 3 March.

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