Can't buy items, go to base, etc.

I can't buy items. They are there, and highlighted like usual, when I click them it makes the little click sound but I can't actually buy them, I also can't go B. Down on my interface the little circle that says "B" and has an image of the "Back" animation is just see through. Also I use smart cast and when I use an ability, e.g Lee Sin's Q, it shows the blue lines that show up to direct your q when you're not using smart cast, like when you press Q but haven't clicked in a target direction yet, but the ability still activates like smart cast, it's weird, pls help.