how do i explain

it's like 4 in the morning and i can't fucking sleep because i have to go to school today and i'm going to get called to the office for skipping last period on thursday. i actually have a good reason but i'm not sure i can even tell the principal it. on wednesday i told my mom and my therapist about my sexual assault. i had tried to block the memory out of my brain for so long and on top of that i have ocd so on thursday after i had told my mom and therapist the story i couldn't stop obsessively replaying it in my head. i was just going over the story over and over again and telling myself things i could have done differently to avoid it. being at school definitely wasn't helping so i skipped 8th period and went on a walk to calm myself down. do i tell my principal that when i get called down or just take whatever punishment he gives me for skipping bc i'm not sure i can even tell him that.