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With your Premium account you can enjoy the service all over the world, even if Spotify hasn't launched in the places you go.
Did you get an email receipt for your subscription purchase? Search for it in your email account. In it, the Spotify username you're paying for is shown:
Logout of the app, and be sure to use that username to login to your account. It's the one with the Premium features.
You can login to the website with that username to check the status of your subscription, and your receipts.