Overpowered Fizz?

I have played tons of games with fizz on the enemy team everygame if he gets a few kills early game and the player knows how to play fizz then he will just 1 shot u with his combo. If fizz doesnt get feed he will still 1 shot u when he gets better farm or gets ult before you. Well some of the games i can say that i tilted and fked up while playing againts fizz but most of the games fizz just is unstoppable if he gets a level advantage or a few kills. I dont know if its just me but just replay