Self harm and cyberbullying myself

I don’t really know why, but I seem to start losing interest in things, things are getting harder to do, and I can’t seem to get a break. I’m kind of tired. I just don’t like life, but don’t want it to end. Not death, just a break which I can’t get. I am a student, for one. I used to be a topper, but now I’m failing all my subjects. I can’t seem to get a grasp; the once easy homework is now like an impossible task. Also, I’ve been bullied in a rather interesting way. They say when someone is bullied, they will punish the bully and help the victim, right? What if I bully myself, which I do both physically and online.