Game not registering commands

League has recently started to not register commands quite often. Things like right clicking when shopping and not buying the item and I have to keep going back to the item to buy it to spells simply not activating. This only happens in League so I'm sure it's not a K/B M problem and I can type just fine.

For example, in an ARAM game I just finished, I use snowball and it hits someone. I press the key again to go in for an engage (it hit, I can see the Summoner Spell icon had changed). I have ~2 seconds to use it. I press the key, don't go in. Maybe I was crazy and didn't actually press it. Press it again. Nope. Mashing it for the last few milliseconds I have left. Nope, it expires and the game goes on. It happens with Summoner Spells and regular abilities. I try to E > Q > AA > R as Graves? Neither the Q and R will activate and I just went ham in a situation that would've won the fight but since it didn't activate, I lose a ton of health and deal nothing