Britney Spears struggled to channel bad girl for new video

Britney Spears struggled to ditch her 'sweet mommy' persona to tap into her inner sexy star while filming the raunchy music video for her new single Work B**ch.

The pop star is preparing to launch an assault on the charts with her latest track, but admits she felt unnatural getting down and dirty for the promo now that she is a mother to two young boys.

She tells E! News, "My choreographer actually, when I was doing the rehearsals for this video, he was like, 'Britney, you are not a sweet mommy in this video. You are nasty... mommy in this video.' And I was like, 'OK... OK!' When you start to feel the character, you start to feel silly, 'cause you're like, 'This isn't me, I'm not like this.' Moving all sexually and stuff like that... As mommy you feel really awkward doing that."

But Spears insists she was blown away by her own confident performance when she saw the footage: "When I watch playbacks sometimes, I'm like, 'Who do I think I am?! Who the hell do I think I am?!'"