What can these hallucinations mean medically?

My friend has been having hallucinations lately. Her vision went black and then kaleidaskoped for a little less than a minute, she heard people speaking to her, and she literally felt someone push on her head when she was laying down(while she felt the pressure she couldn't move, open her eyes, or speak so she just prayed. It only lasted a minute or so). She doesn't act any differently. She's not crazy or threatening anyone. The auditory hallucinations are random and don't tell her to do anything, but are very clear. She' s worried and doesn't want to tell anyone. Any doctors or people who just have an idea of what this could possibly mean. She doesn't seem to have any other symptoms.