Need advice, please help.

[thiarigirl]

I am a lawful permanent resident and have been living in the US since I was 2 years old, I am now 32 years old. My parents became naturalized citizens in 1993 and 1994. At that time they turned in my brother's birth certificate and paid the fee to receive a citizenship certificate proving he derived citizenship from them. My birth certificate was never accepted as the immigration officer advised them they needed to translate it, my parents never got it translated and I recently found out that it never needed to be translated as it was written in several different languages, this went unnoticed for years because of the tiny font that nobody paid any attention to. Fast forward to now, I called the national immigration line several times to see how I can prove my citizenship through my parents and was told that because I was over the age of 18 when the child citizenship act of 2000 went into effect (February 27, 2001) I would no longer be able to benefit or derive citizenship through my parents. I made sure to mention that I was indeed under the age of 18 at the time of their naturalization but was told by information officers it didn't matter and the law that took effect superseded the previous law. So feeling confident that I lost my chances to derive citizenship through my parents, I went ahead and filed the N400 naturalization for citizenship for myself. In the interview, my immigration officer gave me the test and I passed fine, but then she learned that my parents were naturalized and said that if I get a denial letter, then I would know why and that was because I filed the wrong form and that I might already be a citizen having derived it from my parents. She also said that I would lose the filing fee of $680 and have to start all over with the correct form. I tried to explain to her that I was told several times what form to file and she just said she would review it more but was seeming very sure of herself. I walked out devastated and called the national immigration line and explained what just had happened and the information officer advised me I was right and that she was wrong which made me feel much better but everything I am reading states something different and now I am feeling helpless. I don't understand how they can tell you to file a certain form and then tell you sorry its the wrong form and you have to pay another filing fee and submit the correct application. HAs anybody ran into this situation? Any advice would be appreciated.