You mentioned having multiple mental health diagnoses. Unless you are self-diagnosing, this would suggest that you have been in contact with mental health professionals. If you have access to them, you should talk to them about these things. They can help you.
The nature of murder fantasies often involves power and control. They seem to occur among people who are struggling and or who lack power in their lives. Feeling powerless to control certain people or events in your life might prompt fantasies where you envision a stronger version of yourself, a person who can take charge or call the shots. Since I don’t know you, that is only a guess. Certainly, there is more to your story.
I would strongly encourage you to consult a mental health professional. Treatment would help you to feel more joy and less pain and powerlessness. If you were happy you would not think about hurting or killing people; I don’t think those types of thoughts would ever cross your mind. I suspect that you might have a great deal of emotional pain and that is, at least in part, why you are having these homicidal fantasies.
You don’t have to tell your mother why you want to seek help. Ask her to assist you in seeking help and hopefully she will comply. If not, go to the school counselor or another trusted faculty member and ask for their help. They will know what to do. Finally, if these fantasies become overwhelming and or you fear that you might harm someone, call emergency services. They will protect you and ensure that you receive the proper treatment. Please take care.
Dr. Kristina Randle