Of all the good lines in this poem, I think this one is the best:

"I am young and old at the same time. I still hurt because I cannot understand some things."

I think you could write two more poems with each of these sentences as a first line. There's a lot to explore here.

Keep it up.
But he grew old, this knight so bold / And upon his heart a shadow / Fell as he found / No spot on the ground / That looked like El Dorado.