I suppose you redeemed the code using iTunes via computer, not the AppStore via your iPhone. No worries - it happens sometimes. Just click again the buy button to download the app again. You don't have to pay or something since you already purchased the app.
Don't worry. It happened to me a few times before. You just have to wait some time until the information is updated in the system. Once I had to wait a few hours until I was able to review an app.
First of all thanks for the promo awhile back. I finally got time to mess around with this app and left a review up on itunes (as pajo_ojap). I won't go into the same detail but I felt it is a well designed app. Is it worth 0.99...I would think it should be. The thing is, compared to other apps (some very stellar apps) at 0.99 it probably falls a bit short. It's kind of a tough situation as comparatively you're probably getting your moneys worth of entertainment out of it, when compared to other things you may spend/waste your dollar on. I think if you were to add similar magic tricks to the app, with different secrets it might give it a bit more life/value to people. But to the dev, keep up the good work.