I need some help with ongoing school drama?!?

This question revolves many incidences that happened in the this last school semester, so I'll try to keep everything as clear and concise as possible. This whole thing began when me and my friend Kris decided to go to a dance and hang out together (NO HOMO, we're just friends lol) and some people there wanted to meet up with us and they were going to drink some alcohol that I brought before the dance (I brought it because no one else offered). Long story short, they don't ever show up until later, we go messing around until the cutoff of getting into the dance at 8pm, and we get caught with the alcohol. Upon interrogation, we were seperated when asking questions so we wouldn't agree on the same thing, and my friend Kris lied and they took his story. However, when they interrogated me, I was extremely nervous and they sensed this and I told the truth; even if I did lie, I seriously in my mind doubt that they would have bought it. Now my friend Kris hates me. A few weeks later, we start talking again, and theres this girl named Felicity who likes me and told Kris and I that, but I told her that I just wanted to be friends with her for now, which she understood and accepted. Kris on the other hand kept asking me CONSTANTLY and persistenly to go out with her, even after I kept saying no no no and finally I told him to just step off, and he snapped and said some pretty mean things. I then had the dumb idea that if I pretended to go out with this girl for a while, Kris would be happy with me; was he? No. He thought I was faking it because he told me that he asked her to "hold my hand" (which she did, but when I asked if she would) and thought we were faking. Then we get into a text war and say some PRETTY dang messed up stuff to each other; extremely hurtful stuff. I called him after our fighting and asked that if we can't be friends anymore, at the very least I didn't want us to hate each other...which he agreed to (without actually saying). Then soon after this, Ryan, who is Kris's best friend, finds out what happened with me and Felicity and decides to text me his own two cents at which point I snapped and said you know what, thats it, we're taking this to the field after school (all in a COMPLETE impulse, mind you). Anyway the end of the day arrives, I go to where I was supposed to meet Ryan for the fight and before we fought we talked it out and he said we can fight or not, its your call (his EXACT words) and I told him that I didn't want to fight him and we cleared a few things up and kind of just made a truce. All might seem fine, but a few days ago my best friend Trevor was saying that I have a "b*tch" attitude because I called Ryan out and didn't fight him, even though we plainly talked it out and got over it, and now Trevor barely even talks to me anymore. And also, right after the alcohol incident, one of my friends who I had to say was involved with the incident, which he was, sent me a message on Xbox live simply saying snitchhhhhhhhhhhhhhhhhh or something like that. I need some help and advice on what to do, I'm losing my friends and I didn't mean for any of this to happen, I guess we just learn painful lessons sometimes but this is driving me crazy and I can't stop thinking about it. I also don't like living with the knowledge that people hate me. At the very least, someone tell me what I could have done differently. Thank you so very much :)