It is common for your teeth to feel sensitive to hot and cold foods and drinks after whitening. For this reason, we recommend avoiding these things for a few days if you notice sensitivity.
Avoid wearing your trays overnight as this can increase the sensitivity and we recommend using Sensodyne or a high fluoride tooth paste to minimize the symptoms. However, any sensitivity should subside in a day or two.
After removing your whitening trays, try to avoid staining foods like coffee, tea, and wine for at least 30 minutes.