I think I’m self harming

I’m 13.. I posted yesterday day about eating disorders but that’s not this.. I cut in the vicinity of sept-nov 5 times with sharpeners and a razor. I stopped Beacuse of my school telling my parents. Today after a month of being clean I think I did it again.. I don’t know if it counts but I was scratching myself on my arm and it was really light so I’m surprised it made a mark but it did and I don’t really know if it counted - I’ve left a photo here. I can’t tell my parents because as I said they don’t believe in Mental illness and think I’m doing it for attention and I can’t tell my school Beacuse all they’ll do is call my parents. I’ve got no friends to tell.. what do I do help ASAP please