What should I do if I got a MDMA Charge in New York?

Was on my way to a camping trip with three friends, got pulled over going 80 on a 65 on the NY State Thruway. Cop said he smelled burnt marijuana and told us to step out of the car and stand by the hood. He searched the car and found 13 grams of MDMA that we were bringing to the campsite where we were meeting fifteen other people. It was in my backpack when he searched the car, and so I had to take responsibility for it. NO intent to sell but am being charged with Criminal possession of a Controlled Substance in the 3rd degree for unlawfullly possessing a hallucinogenic substance weighing five grams or more. I just got a lawyer and am meeting with him tomorrow, but I'd like to hear from other knowledgable people about this. What do you think will happen, how severe is NY with this? For some added information, Ive had a completely clean record till this incident, 19 years old (Turning 20 a day before my next court date, im a full-time student, junior in college, no job, was just bailed out for $20,000 (Probably very high because I was far from home, and they saw a potential flight risk) If anyone has any information or advice, please let me know. Thanks!