20 Year Old Daughter Might Be Mine

I was leaving for Desert Storm. I resided in Colorado. I got married before I left, but prior to leaving I was told the child was not mine. No Dna test done and I was not put on the birth certificate. I recently did a search based on curiousity and the fact I've raised my other 2 daughters for the past 14 years.

If she is proved to be my daughter at age 20 with dna tests, can the mother come at me with arrears for child support although I was told I was not the father and never was on the birth certificate nor told I was the father. If I am the father after DNA tests......What options does the mother have for child support. If she is my daughter, she is my daughter. Anullment regarding the marriage. Listed as no kids per the mother.