[GAMEPLAY] I Cant Left Click In Game!

So i go to play a premade with 4 other people and when i load up I can't click on anything. I can't buy items or cast my abilities. Seeing as I was Karma I could not use anything but my ult which is useless unless I can left click to cast another spell. Please help. I exited the client and restarted it then it gave me a leave buster warning even though I came back to the game. That isn't even fair. I had to type in a message that i agree even though I most definitely did not agree. I am trying to repair the client now but I'm not sure that will fix it.