Last night I fell asleep with a Crest3D white strip on accidentally. I’m in so much pain I don’t know what to do Is this normal?

I would suggest getting Sensodyne toothpaste and use morning and night to help relieve sensitivity! You can also take the toothpaste and wipe it across your teeth (without rinsing/brushing it off) for a couple minutes. Also, stay away from cold foods for a few days!