Drug Possession: Possession and an Expired License

My question involves criminal law for the state of: California.

To make a long story short I was pulled over upon exiting a public park around 4:00 in the afternoon by two police officers. I was told I was being pulled over for expired registration, but my registration was current and after I pointed that out to the off we he then told me that it was also because of a broken sideview mirror which shouldn't matter because you only need 2 mirrors to be legal. I gave him my insurance and license and my license expired on my 21st birthday while I was living out of state and I didn't get a renewal in the mail and I just moved back a while ago and haven't made it to the DMV. The next thing he asked me was if I had anything illegal in the car and I responded yes because I knew it was already going to be towed at that point and he asked where it was and how much, I told him and figured i would be cooperative. I was then taken from my vehicle and searched and then he searched my vehicle to find nothing else. He tried to accuse me of selling drugs but he had no proof because I don't. He then asked if I had a cell phone I said yes he asked where I told him. Then he proceeded to look through my text messages without my permission and then when that turned up nothing they wrote me up for a possessions charge and told me I was free to go and I would get my car back once I got my license renewed. I grabbed some things and was waiting for a lift when he asked if he could see the ticket he wrote me and I gave it to him and he added the CvC 12500 to it, I should have said no and walked away but I didn't realize he could add stuff to my ticket like that. After I got picked up by a friend my friend was then pulled over and searched by the same officer and he actually knew the officer and while being searched on his person the officer told him that it was because I was I. His vehicle and he proceeded to tell him what he had found in my car. I don't think that is fair or right to target me like that or share my information. I know that the two items I was cited for can be charged as misdemeanors or infractions and I wanted to know how I can get them reduced/ and the penalty. I am 21 and I don't really want this on my record. I had way less than an ounce and a couple roaches in my ashtray.