I'm sure you'll be fine there Tara. As airports go it's quite nice and although I've never slept there the seats look quite comfy with a large selection of restaurants and bars and some should remain open throught the night.
As long as you have a valid flight ticket I don't think any airport would kick you out. I've slept at London Stansted for instance, where there's a large overnight community these days. The link Mongo pointed out is normally very informative, although unfortunately not in your case, it seems.
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