What went wrong, where did I mess up.?

I called my gf and asked her in a pissy attitude why she didnt call me. She didnt hear me the first time so I asked again and started yelling at me. so we started arguing and she hung up. I called her in the car her mom said we didnt have healthy relationship going on. So when she got home I asked her where she was justified in yelling at me and hanging up on me. I dont like being yelled at and I said that if she didnt yell at me we wouldnt have argued and she said if I hadent asked that question we wouldnt have argued now as a bf I think I have the right to ask Sorry if I get a little attitude when I ask but there was no right for her to yell at me.Then I told her she didnt have the right to yell at me. I said I didnt think it was fair and that when she asks things like that I dont yell. She said we're 2 different people. Meaning that she isnt me and she will yell.. or something like that. So does that mean she was justified in yelling at me?Then we she said she expects me to listen to her all the time. I said I wasnt going to listen to her all the time. She said things that I did that wasnt true. So I said she shouldnt lie. She screamed at the top of her lungs for me to leave her alone and stuff like that. Keep in mind her mom was listening and only able to hear her. So her mom probably umed I was treating her like ****. So now I look like the ***, she thinks she's right maybe I was wrong to get an attitude but no reason for her to yell which lead to the arguement. what went wrong what happened?