Should I have a suicide scare?

I have told my mom that I wanted to kill myself and she kind of blew it off and yesterday she saw a hour gl that I cut into my for-arm and asked me why I did it then blew it off. what I want to do is take like 10 unisom (or just enough to go uncontious) and go to the hospital and show my mom that I'm serious. p.s. I have a therapist but she hasnt been working well.