teeth whitening?

i used to use whitening strips and things all the time. i havent for about 2 months now, but i just recently used one, and it was like shocking my teeth, there was shooting pains in each tooth, it hurt so bad, and i dont know why ?...
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you have sensitive teeth.. mine did that as well because i left it on to long and my teeth hurt so bad. i couldnt drink anything or breath in if my mouth was open because it hurt so bad.. it iwll get better in a few days.. but its gunna hurt a lot.. do not use them for awhile.. i left mine off for awhile like 2 weeks i think.. then i started using them againa nd only for ike 15-20 minutes and i slowly went back to 30 minutes and now my teeth don't hurt anymore
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