Infinite regress and debunking karma

[Sicnoo0]

According to the theory of Karma, all suffering is caused by your own misdeeds in a past life.

Let's call the first being to ever suffer Bob.

According to the theory of Karma, Bob must have done something in a past life which caused someone else to suffer.

This means that someone else suffered before Bob ever suffered, which contradicts our assumption that Bob was the first being to ever suffer. 

We started with two premises (Karma is real, there was a being who was the first to ever suffer) and arrived at a contradiction, which means that one of the premises must be false. 

I can't see a reason not to assume that there was indeed a first being to ever suffer, so therefore the premise which must be discarded is the premise that karma is real.

By a proof by contradiction I've shown that the theory of karma must be incorrect.

You don't know much about evolution of the pain response do you ?

What does nociception and biology have to do with karma? 
I'm not understanding so please enlighten me