[Gameplay] Smite Negating Abilities

Basically what happened was i was playing as Lulu, and right i cast my E i was smited by a Lee at the exact instant i cast it and me E went into cooldown, but it didn't go off I.E. i didn't get the shield.

I am not sure if this is specific of a general thing, but this has only happened once. The only way i think you could duplicate it is

1. Someone as lulu
2. Someone with smite
3. Cast the ability in the exact instant you are smited