Redeemed minecraft gift card, can only play demo

Try to find a download page/tab… I had the same problem when I first got MC 2 years ago… I'll look around a bit more for a solution.

Did you download the actual Minecraft to your computer? And remember to login using your email rather than your username

Only the demo is available on the website. You say it say you are registered so you need to login to the site. Once you are logged in, go to the Download section and click on the minecraft.exe link. This will download it to your computer. Find it on your computer and put it in a folder, make one called Minecraft. Click on the.exe in the folder and it will download and unpack the game and you should get a launcher. You need to sign into the launcher using your email and password from the website. You can create a profile if you need to to play an older version of the game but now you should have a big fat play button at the bottom of the launcher and you are good to go. To play minecraft any time then you just need to click that.exe in the folder (I usually put a shortcut on my desktop to make it easier) You said you registered twice so make sure you are logged into the account that you redemmed the giftcard on or it won't work. Hope this helps.