How do i know if i should run away?

Ive been a good kids my whole life i never smoked never drank never nothing untill recentally my life has been going down hilll ever since i tore my ACL and i havent been able to play any sports yes i been sad and ive had alot of free time i jus recentally started drinking i got caught once and i stopped. Now my parents wont let me go out or nothing and very strict! i Recentally also got into a fight with my das and ran away for 2 days and i still didnt do anythign i stayed clean. Im trying to tell my parents that im not going to do it agian and they dont bealive me they been talking about sending me to boarding school and thats why im thinking of running away becase theres no way in hell im going to go there i dont know what to do