The fear of serial killers and being murdered is also known as Foniasophobia. I actually struggle with this fear myself. It is a paralyzing fear and can also be involved with being murdered. This is often triggered by media and true crime documentaries about serial killers or real life crimes. From my own experience I know that people can have certain phobias that fall under the same category. For example I struggle with Foniasophobia, Thanatophobia (fear of dying), and I do have another that I don't have a name for, which is the fear of someone hiding in my house (a murderer.) sometimes I feel this intense anxiety when I'm trying to sleep that someone will come behind me and kill me. I am not sure if there is a specific name for it but I don't even go into some parts of my house at night.