The first thing I would do is hire a qualified DUI attorney in the County where it happened. Unfortunately when the paperwork is orginally filed it almost always shows a 1st offense which will be amended at the preliminary hearing or when the case moves up to the county. It is very important that you talk with an attorney who can go through all your options for a 2nd offense within ten years as well as any possible defense.
My colleagues have it right. Once a background check is done, a correction will be made. The implications for a second offense are serious so you should retain an experienced criminal defe se attorney.
I agree that you should expect that the new charge will be treated as the second offense that it is. You need to have experienced criminal defense counsel who regularly handles DUI cases assisting you in this matter. Most here offer free consultations, so I would advise you to reach out to one or more from your area to speak privately about the situation. Good luck.