should my boss be mad at me?

let me begin, i’m 17 and work part time at dunks (i’m a junior so normally after school) this week i worked monday wednesday and friday (my boss had some grudge against me for taking a day off a few weeks back so she stopped giving me weekends.) i get a text at 8 this morning asking if i can work 10-4. mind you, i woke up and got the text at 9:50 because last night i was closing so i was there from 3-10, no break, and working alone from 4-7 with a huge line cuz the guy i was working with thought i deserved to be stressed by the line. anyways, i replied saying “i’m so sorry i’m just getting this, but unfortunately i have plans and can’t do the shift, sorry” (i’m going prom dress shopping with my mom) and he replied “ok but A (our boss) is gonna be pissed”

should she be mad at me? i’m working tomorrow7-11 cuz i’m covering someone’s shift and idk if she knows that but should she be mad at me? they expected me to not sleep in (im a teen i love sleep) like shes mad i woke up late and im not coming. if i was asked yesterday i would’ve taken it, but i now i can’t. anyways, should she be mad at me?