I have committed
Creo que he cometido un gran error.
I think I've made a big mistake.
He cometido un terrible error.
I have made a terrible mistake.
Padre, he cometido un gran pecado.
Father, I have committed a great sin.
— Divorcio a la italiana (1961)
I have made a mistake.
I've already made that mistake.
Yes, I have made mistakes.
He cometido más de un error estúpido en mi vida.
I've made more than one stupid mistake in my life.