Poor Harry Styles, being a party-loving teen can't be easy when you've got a world tour to do.

The One Direction star was forced to leave the stage mid-song during a concert in Pittsburgh on Monday after what was rumoured to be a "heavy night" before.

A video has now emerged of Hazza crouched down behind the stage appearing to throw up.

The boyband were in the middle of performing 'Rock Me' on their Take Me Home tour when Styles abandoned his post.

The YouTube clip shows 19-year-old Styles wiping his face with a towel before attempting to rejoin his bandmates who looked a little lost without him.

Radar Online reports Harry and his 1D boys rented out a bowling alley the night before their Pittsburgh gig and stayed close to midnight. Liam Payne tweeted the next morning, ”My head hurts…Can’t even begin to remember who won bowling…”

During their night off, Harry tweeted:

Could he have been suffering from a classic case of a excess drinking or, as he told his mate Nick Grimshaw on his Radio 1 breakfast show, he'd simly 'eaten too much before the show'.

Whatever it was he seems to have recovered and was looking much healthier on Friday, as he posted a picture on Instagram of him playing golf with his "golf friends".

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  • 1. He's got lovely, bouncy curls which we'd love to run our fingers through.

  • 2. He's not afraid of getting naked.

  • 3. He's got a rather nice voice, which he could serenade us with.

  • 4. He was the cutest kid ever - just look at those cheeks!

  • 5. His bromance with Nick 'Grimmy' Grimshaw. We heart a good bit of man love.

  • 6. He scrubs up well in a suit. Yum!

  • 7. He loves animals *melts*.

  • 8. He gave Taylor Swift enough material for about 10 more albums during their relationship.

  • 9. He has tattoos. Lots of tattoos. OK, many are questionable but it just adds to his allure.

  • 10. He loves his mum. Bless!

  • 11. He always gets the best girls (we love Flacko almost as much as Harry).

  • 12. He's part of our favouritest band ever (ok, this week) - One Direction.

  • 13. He's got a filthy mouth.

  • 14. He's got some flashy cars. And a Capri. This is very cool indeed.

  • 15. He's not afraid to make a fool of himself (yes, that is him inside that thing).

  • 16. He's touchy feely. Especially when it comes to his bandmate's bits.

  • 17. He's the Robbie of 1D.

  • 18. He's charitable - 1D are releasing this year's Comic Relief single.

  • 19. He'd be an amazing mate. We are sure of this.

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