I went to redeem my free Minecraft Windows 10 version, and when I signed it and redeemed the code, it told me that I have already redeemed the code, even though I don't think I redeemed it before. How can I tell that I've got the Windows 10 edition? Is there a difference that I can clearly see? I already have Windows 10.
Added (1). I might have figured it out.
Will give updates
Added (2). Thanks to Dominic for answering the question.
Though I did find that it said the price. So i clicked "free trial" and then it said I installed it.