Should I tell my friend that I deliberately terrorised him and that it was me years ago?

This happened almost 8 years ago. My school had a free Spanish course at night and I wouldn't attend, but I set up a plan with someone to scare my friend. When he went to the bathroom, I was told he was in the stall, so I went in without my shoes on, my feet covered in red paint, and started laughing hysterically. He was silent and just lifted his feet up. I started running, laughing and screaming (he said he started praying and begging for mercy for it to end soon) then I stopped suddenly, started saying "open up, I know you're there" and left the place. The teacher came in later, but when he came to him, he had found him in a state of shock, crying and shaking, so I went home and to this day I haven't told him, and he ALWAYS tells everyone about it as a paranormal story, like to anyone... There was one day when he was talking about it in a whatsapp group and I was laughing my ass off but I think I should tell him one day