Define Self Harm

I have no idea where this goes, so move as needed. I just wonder what defines self harm? Recently I ve been wondering if scratching, pinching, etc is self harm, and whether these things are exceptable/helpful /bad if you leave no marks, and don t draw blood. Weirdly, I guess I was thinking that it would help me be more in the present and feel better...my arm is pretty red now . Deep breathing, etc just doesn t seem to work for me, especially when I m driving...now I just feel guilty and... Define Self Harm
https://www.myptsd.com/c/threads/define-self-harm.50274/