What is the hardest job you have ever had?

After graduating from high school, I went to the construction site to move bricks because I didn't get into college because of my poor grades. Bricks are heavy, and I feel a thousand pounds on my shoulders. I have never done heavy work at home. So after a whole day, my efficiency is far less than others, my feet are blistered, and my shoulders and back are particularly painful, as if they don't belong to me.