Trigger warning - Parents found out about self harm

So, my hoodie sleeve fell up my arm by accodent and my mother saw the cuts, I tried to avoid it when she asked. Later today she asked again and I really am not comfortable to be talking about it with her or any one. I’m not particularly comfortable in sharing stuff with people, especially her. She’s not a bad person but I just can’t. Tomorrow she’ll probably ask again, I’m so scared. I feel it’s just going to make me worse. It’s my coping mechanism instead of suicide, I don’t know what to do. I’ve school tomorrow aswell. (I’m 16)

Please anyone give me suggestions, I don’t want her asking me about my feelings, it’s all my personal stuff