Ziggs Q invisible

I was just playing as snowday ziggs against a golden alistar in urf when my Q became invisible to everyone including myself about 7 minutes into the game. In midlane alistar used his W+Q combo on me while i was in the process of using my Q from the dragon side midlane bush, i believe i landed directly on top of him but i'm not 100% sure. Immediately after my Q became projectile (the snowball) became invisible but i could still see the bounce and explosion animations. My Q still did it damage and proced items.