Ok, new thread i got busted and im unclear of how my age is going to stand in court!?

Ok, so i got pulled over for no tag lights, i had been drinking and smoking and had my smoke and the seeds, in 2 different bags. Now the cop didnt charge me with DUI becuase i was driving perfectly fine and i told him the truth, but i still got arrested for possesion under 20 grams. So im in the state of Flordia and i turn 18 on the 16th of may and this occured on the 11th. Im still a juvi. on this occurance correct? and depending on that, what kind of sentancing am i going to be looking at, and do they have the right do recon on me? i need to know these things for an ease of mind, i just like to smoke man. i didnt mean any harm!