I tried to kill someone instead

Is it count if I tried to kill someone, not myself? Fortunately, the attempt failed or i probably live with guilt and maybe trying to kill myself. Here's the story. The person that i try to kill is my adopted mother. I mixed her drink with floor cleaning solution. Thank god she just vomit and sick after that. I- I dont know what will i do if she die from it. I might confess to police or kill myself out of guilt. I never tell this dirty little secret to anyone. 13 years later i was diagnosed with ovarian cancer and unable to have children. This is probably my retribution for my sin.