[CLIENT] unable to left or right click after loading into game

Just encountered this bug, rather upsetting as it was a ranked game and I got assigned a leaver penalty for it. Champion selection went as normal, and once the game starting loading in I tabbed out to pull up some build information on another monitor. I tabbed back into the game before spawning onto the rift, but once I was on the rift I was unable to click at all, or even type a message to my team explaining what happened. The mouse was also the default white triangle, not league's gauntlet. I attempted to tab out and back in to fix the issue to no avail, and killed the process with task manager. I tried to load back in, but the match was remade by that point.