[GAMEPLAY] Morgana Ult Goes Off When Nobody is Around

I was playing an ARAM as Morgana. Was being silly and on enemy sides and used my Zhonya's when Zed came at me. I instinctively hit my ultimate, while still in the Zhonya's, and Zed went out of range, making my R no longer lit up, but when I came out of the Zhonya's my ult went off and didn't attach to anybody because there was nobody in range.

The circle showed up and then immediately disappeared.