1. I don't know.
2. He knows that his prophecy is that he will kill his father and sleep with his mother so he runs away from Corinth because he doesn't know the King and Queen of Corinth are not his real parents. Throughout the play, he finds out that he is the father and brother of his children.
3. There is now a family curse which is shown in the play, Antigone.
4. Yes, he would have been very different.
5. At the end he is blind but now he sees the truth. Irony.