Truly as Shira pointed out, the Bible forbids making marks upon your body, so I would think twice. But moreover "I AM" is the closest translation to the name of God, in Hebrew, and that is why there is no verb "I am" in the present tense. Only God is the ever existing one, so I would certainly refrain from applying such a name to your body. Just a word of caution. It is of course your choice, but think twice.