What charges will i get if i get arrested for possesion of perscription narcotics and if im a minor in NJ?

it was my second affence i got arrested twice in 3 weeks 1 for something really stupid and the other for having percocets, i wasnt read my rights and i was mug shotted and finger printed which i dont think there aloud to do and i dont really wana be on probation for a year if i even get that soo can someone tell me?