I used nair face cream and i've had irritation and redness for almost 2 hours. when will this get better?

Hard to tell: Nair cream is not generally well tolerated, especially on the face. Irritation and redness after use is common reactions. How long it will last depends upon how sensitive your skin is and how severely you react. Make sure you have washed all the nair off your face, use gentle soap like Dove and lots of water. Apply soothing moisturizing face cream. Avoid using Nair in future.