Question about whitening my teeth with NiteWhite?

I have been whitening my teeth for 3 days now with NiteWhite ACP but am seeing no results yet. It has 10% carbamide peroxide. I was told to use it about 30 minutes a day (once a day), but after doing a bit of research online it seems like I may have been told the wrong thing. From what I've read the 22% should be worn at least an hour, so if I'm on the 10% shouldn't I be wearing it like two hours or more each day? I have no instructions because I wasn't given any kind of NiteWhite box or anything. I really am feeling like I might not be wearing it long enough because I'm not even experiencing any sensitivity whatsoever. Should I start wearing it longer?? Thanks for any help
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Yes, the 10% one is less strong. Therefore, you should use it longer. However, discontinue or reduce the length of time if you develop any sensitivity of teeth. More info on bleaching : http://www.associatedcontent.com/article…
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