For some reason I still think you can't get away with that.
You can smoke at any age, its your right. However, you are prohibited by law from buying cigarettes below the age of 18. Whoever gets caught selling cigarettes to minors can face serious fines and jail time if convicted.
Other than that, the only thing a cop can do is ask you where they got them from and call your parents, which is unlikely.
The government sucks ass at trying to regulate what minors can and can't do. In my opinion, you should be able to drink, smoke, drive, and join the army at the age of 16.
Again, this is for Americans.