Client issues and 1 bug in game

Client get very slow over time, If you wanna swap interface to champions or shop or even typing reaction timer is low after a while. Champion select reload slow. Is there something heavy in the system that cause these issues?

Bug: Level 2 on first minion wave should always be impossible, but lately i hit it a few times without killing early a ward or jungle mob. notice that when opponent said? how you were mid with me whole time, you can see game with vs Casio on my logs.