If you gotta charge when you were under 18 does it still come up when you're over 18?

It depends on how the charge was handled {in what court} and the type of charge; traffic, misdemeanor, or felony. Traffic violations stay on your record typically for 10 years, unless it's a driving/drinking arrest which vary by state from 25yrs to lifetime. Misdemeanors and felonies {which can be traffic related} depend on whether the charge was adjudicated in juvenile or adult court. Juvenile records are typically expunged at the defendants age 21. Adult court records remain on file forever unless ordered otherwise as part of sentencing or appeal. Best luck to ya!