Am I in The Wrong?

So last month a girl on my bus that I was okay with started gossiping and bad naming my very good friend. This girl on my bus knew I was friends with my very good friend and proceeded to talk extremely loudly about my friend. So, I recorded her talking about my friend. Now to fill you in, this girl has been talking about my friend for months because her boyfriend likes my friend. Any time my friend confronted the girl on my bus about her gossiping, the girl denied it. This has been going on forever so, I record because the girl will just make me seem bad and that I am lying. Caught her in 4k lol. So, I sent the video to my friend. My friend sends it to everyone, the girls share the same friends so of course, it got to her eventually. The girl gets mad at me for recording, her voice, not her actual face or anything. She tells me that I'm messed up for that and I shouldn't have told my friend anything. So now it's current time and about 2 hours ago from me posting this where she came onto the bus screaming and crying about her boyfriend breaking up with her. The girl goes into vivid detail and everything after I ask her a simple question. Is she okay. She just went with a snarky attitude and was like, why are you going to record what I'm saying and tell everyone again. I replied to her with, no I'm just asking if you're okay because you seem distressed. I left it as that. I may not really like the girl but, she was literally wailing and crying so I asked her a simple question because I felt bad. Now I'm upset because I should've went off on her telling her that I didn't send it to all of her friends and that if my friend did that it was not my fault, she should've just stopped talking about her. In the recording she talked about my friend's eating disorder and saying that she was a whore, just a bunch of wild stuff lol. To clarify, my friend was in the hospital and came back the day she said all of this on the bus. She also called my friend a whore because the girl's boyfriend or well now ex-boyfriend, likes my friend. Anyways, instead of punching her in her throat once we got off the bus, I called my other friend to see her opinion. I feel like I should've minded my business with her boyfriend stuff but, I also feel like she didn't have to be that rude and I should've said something back. But in general, I'm gonna stop being nice to people.