Teeth Whitening Help?

I use opalescence tooth whitening gel, but that's not important, when you whiten over night, do your teeth hurt really badly?? Thanks!!
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Got to your local drug store and buy "sensodyne" toothpaste (it's a brand name) and just smear it on your teeth leave it on for about 10min. Then use sensodyne during routine brushing. Make sure when you put the gel in your trays that you stay away from the gum line. Good luck!
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