Painless Wounds

It amazes me how one deep wound
Won't hurt you much at all.
But one small scratch from one small thorn
Can make you scream and fall.

When something hugely bad would happen
There is not much pain at all
It's like that thing had never happened
As if defying the gravity law.

But what about those wounds that kill?
They leave not one scar.
I'm talking about the worst pain of all,
The pain of a broken heart.

A broken heart leaves no cuts
It doesn't really bleed.
But it hurts so bad deep down inside
Healings like a need.

Why do the big wounds hurt so much less
Then those that don't leave marks?
This is one question I will find the answer to.
This is just the start.