Estelle: 'I can't get any sleep'

Estelle has claimed that she hasn't been able to sleep since reaching number one in the UK singles chart.

The R&B star has been at the top of the chart with Kanye West collaboration 'American Boy' for four weeks, but the "adrenaline rush" has caused plenty of late nights.

She told the Daily Star: "I’m always up and I’m always tired, but life is so exciting at the moment. It’s like a constant adrenaline rush."

However, the singer said the sleep deprivation wasn't worrying her, revealing that she often works late into the night anyway.

She added: "Most of my thinking is done at night. You shouldn’t be surprised if you see me on my Blackberry in a nightclub in the early hours.

"I’m getting my ideas and thoughts down and replying to emails. My mind is always going.

"I can get a call at 2am and the person on the other end is like: ‘Sorry, did I wake you?' and I’m like: 'No, I’m wide awake'."