Drug Possession: Possession of Marijuana and Paraphernalia in Maryland

My question involves criminal law for the state of: Maryland

This all happened in Baltimore County. A friend and I were standing outside of a car one night smoking a cigar. A cop pulled up and asked what we were doing. We said we were just hanging out. The cop said he can smell weed, and searched all the around the car and found nothing. We honestly weren't even smoking weed. We told him he can search us and although he didn't search us, he proceeded to go inside the car and search in there. He saw a small purse that I had and found a little bit of marijuana in there, much less than a gram. I didn't even know that I had that in my purse. He also found a small keychain that turns into a pipe if twisted the right way that I got from Argentina while studying abroad, and he took that also. He told me that I'll get a possession of marijuana charge and a possession of paraphernalia charge that night, took down my information, and told me that a summons to appear in court will be sent my way soon (I walked away with nothing in my hand). The other person didn't get charged. That was on August 25.

Today, October 22, a police officer called me saying that he has the summons to appear in court to give me. I met him outside and he gave it to me, and my court date isn't until March 7th. I have a prior DUI charge I received in Virginia back in Nov. 2010, but nothing else on my record. I am a full-time student planning on graduating in May 2013. I really cannot have this on my record considering medical school applications and everything. I'm also pretty much flat broke so I won't be able to afford anything except a public defender.

I've heard of diversion programs available for first time drug offenders. What are my chances of getting that option through a public defender? Are public defenders any good at all? Will they able to get the job done like a private attorney would? If not, what would be my most likely consequence? Thanks so much for the input.