Is AUTHOR wrong in the post ? POST : Happened about a month ago and my friend is still angry with me for it. I graduated college last spring and moved back home but my long term girlfriend and big friend group still live near the school. I was visiting because my girlfriend's birthday was on that Saturday. 

Late Friday night my friend (we'll call him Joe) who lives there texted me saying he has something very serious to tell me and wanted me to call him in the morning. He kept texting me about how its really serious and I started to worry. I wanted him to just call me and tell me that night but he kept saying he wanted to wait for the morning. He assured me no one was in immediate danger and that it could in fact wait til morning. 

Joe lives a street over from my girlfriend in a sorority house, as he's subletting from a girl studying abroad. Due to some previous history my girlfriend does not like when I go to that sorority house, so I usually try to meet up with Joe at our other friends house. 

When Joe realized I was in the area he instead wanted me to go over to his house in the morning so he could tell me in person instead of over the phone like he originally planned. This morning was the morning of my girlfriends birthday, and I had a long and exciting day planned for us. I did not want to start the day off on the wrong foot by immediately leaving in the morning to go see my friend in the sorority house, so I instead called him like we originally planned. He told me the news, which was admittedly very serious. A mutual friend of ours has been inflicting self harm and Joe wanted to make sure I knew so I could help be there for our mutual friend. The phone call lasted about 8 minutes, in which Joe explained the situation. 

Joe is still mad at me because I was prioritizing my girlfriend on her birthday, but the original plan was for him to call me anyway. I didn't think it would be such a big deal if it was over the phone instead of in person especially after Joe said no one was in immediate harm but he still thinks it was a crappy thing for me to do. AITA?