There is case law that indicates the court did not intend for juvenile adjudications of delinquency to count as a prior criminal conviction so this new charge should be your first. You should contact an attorney.
Most juvenile records are expunged pursuant to code after a period of time. Regardless it should be treated as a first offense. If you would like to further discuss your options feel free to contact me.
(540) 840-8470 - cell