Changing one's age

In Pakistan it is possible by unfair means to reduce your age on a official level. So 5 years ago when I was I a child 12 or 13 years old I don't have much knowledge about Deen, what's right, what's wrong. I wasn't aware of the result of the act my father did. Five years ago my father reduced my age just by one year. So now I'm 18 but according to legal papers I'm 17. And because of that act I have to lie every where I go. I can't reverse the act because if I go and increase my age then all my educational degrees would become false and fraud. So I feel very guilty about the act my father did to me. I have to lie everywhere and I am facing a lot of problems because of that act. My questions are:

1. Is my father responsible for every sin I earn because of telling lie about my age?

2. What should I do? lie my whole life?

3. I've forgiven my father but I can't forget what he's done to me. So tell me a way to forget.