Who’s at fault here

I was told at 1:30 AM last night that my mom reserved some beach spot or something for us to go to at 10. Dragged myself out of bed this morning, everything hurt cause I planned on sleeping in, at 11:30 she’s just now ready. I told her I can’t go bc my job starts at 12 and she’s irritated and has her feelings hurt and told me that “I don’t respect her time”. Who’s wrong here?? She’s still going with my brothers and father.

Edit: the beach is down the street, so originally I was gonna spend 90m there or so and be back home in time for virtual work.