Zoe Q hitboxes?

I ended up playing a ranked match with a Zoe mid. her Q seems to be bugged, because there were 2 times I saw her send out a Q , ult towards a sleeping enemy, Q again, and the skillshot went THROUGH the enemy, dealing no damage and just not hitting at all. This only happened when the enemy was asleep, in the river, and she used her ult to try and land a Q.