I was just whitening my teeth with custom dentist trays and hard a sharp random pain?

It was just one sharp pain, what could have happened?
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Usually, the teeth whitening whitener is safe, even teeth whitening sometimes improves your gums health. Most people experience little discomfort or pain after teeth whitening treatment. But over-applying teeth whitening whitener may cause temporary irritation and sensitive for your teeth and gums. Your teeth and gums may experience some minor discomfort or minor pain. however, the discomfort or pain should subside within 24 hours. If needed, an anti-inflammatory may help. If the discomfort or pain lasts for more than 2 -3 days, consult your dentist for more options. Attention : The patients who have sensitive teeth must use a milder version of teeth whitening whitener formula. Patients who are allergic to peroxide should not consider traditional teeth whitening methods. the site give me a lot of help, u can visit it http://www.teethwhiteningbest.com/teeth-…
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