I feel like sh belongs on my body and it makes me feel worse abt myself

Ever since I first learnt what sh is i felt like this is what I should do, like this is a proper punishment for every mistake I do. When I looked at my body it started to feel empty, too clean, like something was missing, too naked even when I was clothed. But I know this isn't normal, all day I'm only thinking about harming myself. These thoughts are not only making me crave sh more but also feel worse about myself. I crave it so so bad, how terrible of a person must I be to the point im aware of it and very much aware of the punishment suited for me