Which region's game am I playing?

Hi, new to the forums here and I have a question I need answering.

I want to pre-order the digital collector's edition of Heavensward but I'm unable to work out which version of the game I am playing and I know that Heavensward is region locked. I believe my account was signed up on the EU site (although it may have been the US one) but I am currently living in Japan. I bought the game off of the Mog Station which was in English and has no option to change the language leading me to believe that it is the US Mog Station however all the prices are displayed in Pound Sterling (GBP). I purchased the actual game using Crysta however.

Thank you in advance for any help.

You can check this by going to: http://account.square-enix.com/

After logging in click on "Account Information" on the left (under the Square Enix Account section). It'll probably ask for your date of birth, but then afterwards it'll show your county/region that are registered on the account (neither of which can be changed, only the actual address within the country)

Thanks a lot!