Why are the cars trying to kill him

Well, it's not bad for a beginner, something actually happens and the character performs flips and stunts with a consistent idea of gravity and space. I am irked by the fact that when he goes back there's a completely new cliff backdrop and I do wish there was just a bit more story, like a start to his running to show us what's going on. The ending was pretty nice and funny, though I can't read the Turkish.
This is good as far as these animations go, you're actually having things happen and putting in effort. Keep it up and keep practicing.