Congratulations. Take it easy, you got a lot of miles ahead.
When I was eighteen, we were able to drink, as they had lowered the age from twenty one. People were able to go and die in Vietnam, but were unable to buy a beer. So, I guess they figured they would let the kids drink.
When I was stationed in Virginia, you had to be twenty one to get "hard liquor" but could purchase and be served beer if you were eighteen.
It was weird, but we had pretty good drugs back then, and that certainly compensated for the slight. No idea what the poor bastards over in the Middle East are doing for recreational consumption these days.
We had the hand stamps as well.