David Tzall, PsyD, a licensed psychologist explains emotional self harm as what people intentionally cause themselves emotional pain, distress or suffering.

“It revolves around internal emotional turmoil and negative thoughts,” he says. “People engaging in emotional self-harm may not necessarily intend to cause physical harm, but they instead harm their emotional well-being, self-esteem, and mental health.”

Self injury is a physical kind of self harm. Nonsuicidal self injury (NSSI) denotes that someone's actions which hurts their body without intending to take their life.

Older research from 2014 notes that NSSI is particularly common among individuals who engage in self criticism and self directed negative emotions.

“Emotional self-harm can link to or may lead to physical self-injury,” says Tzall. “A person may use physical self-injury as a means to cope with emotional pain and distress.”

Sources: https://www.medicalnewstoday.com/articles/emotional-self-harm#what-is-it