Rihanna during her concert "Loud Tour" in Paris (Pic: Splash)

Rihanna during her concert "Loud Tour" in Paris (Pic: Splash)

STRESSED Rihanna’s been put on health watch ahead of this weekend’s Capital Jingle Bell Ball event.

Mercury record label execs are insisting she has 24hr surveillance – and a curfew – after flipping out last weekend in a tearful rant to Beyonce.

A source said: “She’s filming her Loud tour DVD in December and her team is determined that she looks, acts and performs at her best.

 “They are currently in talks with Mariah Carey’s trainer, Patricia Gay, to fly in and start training.”