Use the school's phone then, contact anyone in regards of law enforcement or CPS, wait for them to pick up, and describe the situation as thoroughly as possible, and let the boys in blue deal with the situation.
I feel so friggin shitty rn, my parents wouldn't let me have privacy when I was changing and plus i kinda feel like kms again. On top of that, i think my dad bodyslammed my neurodivergent brother for some reason; (Watching "FNF killed my grandma" rn); Tired