First Time Possession of Marijuana in Alabama

My question involves criminal law for the state of: Alabama

My friend and I were parked near a neighborhood (stupid decision) and had just finished smoking a joint a piece when I (the driver) noticed a cop pull up. I waited for him to come to the window and he could obviously smell weed when he came to the window. He asked me what I had been smoking but I only shrugged and said something along the lines of I'm in trouble. He took me out of the vehicle cuffed me then asked if he could search my vehicle. I allowed him to do so in which he found 1 gram of marijuana. I and my friend were arrested and booked for possession although I was not read my rights. I am 19 and my friend is 16. Will I face jail time, probation, or can I get the case thrown out?
I'm also wondering how I should defend myself, should I plead youthful offender because I hear that the age has to be under 21 or is that a bad decision?

Thank you.

forgot to add he had probable cause to search the vehicle because he saw the finished joints.

You definitely should consult a lawyer to see if you qualify for a first offender program, or another disposition that could allow you to avoid a criminal conviction. I doubt that you'll be going to jail over a first offense, but it's a good thing if you can avoid a conviction.