Teeth whitening does not damage your teeth.
The whitening process uses active ingredients to temporarily open pores in your teeth and lift stains. After each whitening session, your teeth naturally remineralize and rehydrate.
Sensitivity after teeth whitening is normal.
60% of us have naturally sensitive teeth, most often caused by genetics, thin enamel, or crack/damaged teeth. During the whitening process, it is completely normal for teeth sensitivity to occur. The teeth become temporarily dehydrated which reduces their ability to insulate the nerve from changes in temperature. Sensitivity will disappear 12-36 hours after whitening.
The best time to whiten your teeth is just before bed.