How long will my circision sensitivity and pain last before it goes normal?

i got circised about 8 hours ago it's sensitive and it hurts a lot, how long will it be beofre the pain stops and so it just tickles when it touches something instead of hurting, the doctor said on the leaflet i can go back to school after 2 to 3 days so it shouldn't be that long? thanks for the help I'm only 14 so yeah