why did two of my teeth start to hurt really bad when i was whitening them??

it was like a really sharp bad unbearable pain and i almost started screaming. i have this gel stuff in this tube and it is called 5 minute whitening. i've used it before with no problem, but this time was different. i always put it on for about 20 minutes instead of just 5 because i want my teeth to be white for school tomorrow. i was just sitting there on my couch watching t.v. with the gel on a paper towel folded over my teeth and like, in a split second there was hecka pain. now, whenever i bite down, they hurt a little as if i was eating/drinking something really hot/cold. (i have sensitive teeth) . that's the perfect way to describe the pain.... it was as if i was biting full on to an ice cream bar for a second to long. have you ever felt that?? it sucks!! did i leave the whitener on way too long? thanks for any help... oh. also, so i don't use another 5 points on a question... does anybody know of a way to replace the screen on a samsung glyde? or have any suggestions on where to take it to get it fixed? thanks. =]
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Some whitening products use chemicals that can weaken the enamel on teeth, but you didn't say if the pain was concentrated in one area or everywhere. If it is concentrated then you might have hit a cavity, and if it was not, as in all of your teeth were hurt, then it may have been a sensitivity issue with your teeth. Remember the chemicals in the teeth whitening products are supposed to be strong enough to make something as hard as stone, whiten in 5 minutes. By using it for quadruple the recomended time you probably exposed yourself to a certain chemical for longer than intended. Either way I don't think it is something to see the dentist about, just use it as recomended from now on or, stop using it. If the pain still continues then go see the dentist. As for the glyde question I have no idea what that is.
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