Diamonds or coals

Have I got everything I want? No, I haven't.
I feel so tired. I have climb all the way to a mountain top and come back down with my back loaded with coals.
Where have all the diamonds gone? Did I left them on the way? Or did I forgot to bring it all with me?
My face and hands are smeared with coal. My whole body screams with pain and exhaustion.
Was it worth it? Is this what's left of me? Had all of the effort gone wasted?
Should I climb back and search for what I've lost along the way? Can I make it for the second time? Do I still have the energy?
...Why didn't I be meticulous at the first place?...