Killing the same person twice in a short period should have reduced bounty

I just had a game vs. Tryndamere. The enemy Vi dived me under my turret with him at level 4. I started walking back to lane, and Tryndamere and Vi came out of the brush between the towers and killed me again.

I'm now two levels behind. I go back to lane, and I get dived by Tryndamere under my tower, because he's level 7 while I'm level 5. He barely doesn't get the kill, because he's bad. Had he been good, I would have been put in a scenario where I can't even enter my lane, as he can dive me under my tower.

That's really not okay. There should be either reduced reward, or a reduced penalty to the killed champion when this happens. With how fast things die right now, doing this can completely invalidate an enemy champion.