So sorry if this doesn't make much sense but I'm currently crying as I type this. My mom came home and we got into an argument as I had informed her prior I would be out on new years evening for a party. Well my ride there consumed alcohol that I didn't even notice until texting my friends prior to making this post and as it was nearly 4 in the morning and no one else had a car I ended up staying over and texted my mom that this event was unforseen by me. 

During the duration of the party I kept texting her to let her know I was alive as I couldn't call her due to a cold that stripped me of my voice.

So I get home and she goes off on me for leaving my diabetic 18 year old brother at home and for not asking the person who drove me what their plans were, even though I didn't realize they planned on consuming alcohol and when it reached 4 they just announced they were going to bed and the only other person that reasonably had a car left hours earlier due to having work the next day.

For some background info, my bro got diagnosed as diabetic 2 weeks ago, roughly, but it's merely symptoms of diabetes due to a pancreatic infection as the doctors put it. Still they have to treat my brother as if he has diabetes (this includes insulin shots, portion control, pills, etc). My brother is insanely capable of administering g and doing these things himself without my supervision. But my mother seems to believe that he can't and thought about pulling him from high school for some period of time because she was concerned he can't do those things by himself.

Essentially she said that I was in the wrong and chalked up everything to me having a cushy life since she could simply pay my tuition and be done with me. I lashed out and dropped some emotional baggage as a result and made her more mad and said I was further in the wrong for not coming home on time, finding a ride home, or asking my ride (who also hosted the party at their place) what they were planning on doing. So AITA here or did I overreact?

(I'm 21 and in the US, if that helps. I'm only at home for the holidays.)