AIO. dropped one of my friends because shes snitching about me smoking

I have always reallyyy struggled with school like studying and trying to sit still in class and just attending in general. School just really isn’t for me but whenever I smoke before school I find the day goes by so much easier for me and I’m able to focus in class and actually somewhat try. So most mornings before school, I wake and bake or I also smoke during my break as im able to go outside of the school for lunch and ive been doing this since just before Christmas. My friend yesterday brought it up to me and i know shes just concerned but shes planning on telling the school about what ive been doing and this is gonna completely fuck any momentum I had going. I finally feel like I’m going to go somewhere school wise and I know what I’m doing can’t last for ever but I just wanna keep it this way until I leave Highschool So when that conversation happened I ended up dropping her and I do feel quite bad about it and I’m wondering if I’m overreacting?