My recommendation is to sit down, in person, with an experienced attorney in your area. In my opinion, this forum is not the best approach to dealing with such a serious immigration issue. Falsely claiming to be a US Citizen is a very serious charge and could potentially bar you from obtaining any future immigration benefits.
Hire a experienced immigration lawyer to help you out. Claiming to be a U.S. Citizen when you are not is a SERIOUS OFFENSE!! Seek attorney representation immediately!!
Garmo Law Group, PLLC (Michigan) 248-626-0050. This advice is only general in nature and does not constitute an attorney/client relationship. Speak to an experienced attorney before making decisions.