Garen Q bug [GAMEPLAY]

So in a few of my ranked Garen top games, I've encountered a bug where if you try to attack the enemy nexus after using Q, you stop auto attacking until Q goes on cooldown. You just stare at the nexus or walk around it. This hasn't occurred to me before, and can be a real game ender (I was fortunate enough to have enough minions with me to finish the job after my bitter demise).

After I started writing this, I loaded up a bot game to test this and the strangest thing happened. So I got to the nexus, I did the usual thing: auto attack then Q, and it did the same thing as before, it wouldn't let me attack it, just inched a bit closer to the nexus. Then, after a while, it FINALLY decided to Q the nexus, and after that, it acted like normal, letting me auto attack and Q as if nothing had happened. I was using the Dreadknight Garen skin (I used this skin in my ranked games too).

I did another attempt of this, this time using the default Garen skin. Same thing, but this time I figured out how to get the bug again: Move away from the nexus, Q then run towards the nexus right-clicking it once. He does the same thing, stands there, inching forward a bit, until his Q goes on cooldown. I can recreate this every time.

Both bot games were as follow: 5 on my team, none on the other, using runes, masteries, summoner spells and items I'd never use/get in a normal game just to speed up the process.

Scenarios: Right-click + Q, standing still: Garen stares, inches forward, then finally hits the nexus with Q. Q + right-click, right next to nexus: Same as above. Both scenarios above would continue as normal (intended) after he finally Q's the nexus. Q + right-click, some distance away from nexus: Stares, inches forward, until Q goes on cooldown.

Not counting the bot games, this has happened in 2 recent ranked games.

Bonus: If you E, then recall, your E animation continues and so does its damage. Intended?