I came to the in 2004 from my country when I was 14 years old and that time my dads wife filed for both me and my dad she filed as my step mother. My step mother at the time along with my dad was my legal guardians but only my step mother was a citizen... Since she filed for me is there a chance I could already be a citizen of the US? Now I am 22

What did she file for you? What do you show as proof of citizenship?

Here is the info: http://www.uscis.gov/portal/site/uscis/menuitem.5af9bb95919f35e66f614176543f6d1a/?vgnextoid=c7070eaf3c4be210VgnVCM100000082ca60aRCR D

You came as dependent, the easy way to find out is to check with your dad. If he became a US citizen before you turned 18, then you are one.

You can only get citizenship through your step-mother if she formally adopted you. If she did not adopt you, then you did not get citizenship through her.

You can get citizenship through your father if he naturalized before you turned 18.

Otherwise, you are not a citizen and you need to file for naturalization yourself, if you meet the requirements.