EstelleR&B star Estelle has revealed she’s hardly slept in the four weeks since her new single topped the UK charts.

The track ‘American Boy’, featuring Kanye West, hit number 1 in the UK on 23rd March and Estelle told the Daily Star recently: “I’m always up and I’m always tired, but life is so exciting at the moment. It’s like a constant adrenaline rush.”

Plus since moving to New York from London, “I’m back and forwards like crazy to the UK. I don’t get time for sleep. But I’ve so many stamps on my passport it looks really cool.”

But she doesn’t mind the insomnia too much: “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’.”