Weird in game lag

So around 3 days ago I was playing a game of ranked and it was working fine. No lag, no crashes,etc. Starting from 2 days ago, whenever I queued up for a game, it would be fine. HOWEVER, in game there would be a weird lag spike where everytime a minion dies, its still alive with no hp and the minion auto attacking animation can still be seen on my screen. The game would stop for a while and then continue about 5 seconds later. This would also happen whenever I engaged, making the game impossible to play. Does anyone have the same issue? If so, what did you do to fix it?

P.S. sorry for being bad at describing but basically my game just lags a lot when my wifi is working fine P.S.S. I'm on mac El capitan if that makes a difference