Wasn't it so that kills gave just little XP?

I was playing my top lane with 15 cs ahead in farm, but my laner had 2 kills and 1 assist and he was 2 levels ahead of me. I mean I can understand it gives him a level playing field or maybe even a small advantages, but 2 levels on 2 kills and an assist, seems a bit much? Meanwhile I am 15 farm ahead and he just comes back to lane from a disaster on mid, but still, my lane ruined because of what mistake I made? Recalling when I am supposed to? Maybe I just didn't TP fast enough...