Im cutting myself because i need help

This is going to be a bit of a vent, so stick with me here.

Since i was 8 years old ive dealt suicidal ideation and depression. This was at the time of the pandemic. Though my mom definitely took care of me and helped me with my mental health, it really only helped me trying to not actively kill myself.

In 2 weeks ill turn 14 years old and my mental state hasnt changed much since then. Sure, i dont cry myself to sleep everyday now, but i still struggle with suicidal ideation and the depression. It also doesnt help that i live on the 14th floor.

Around 3 weeks ago, my mom finally gave me antidepressants. (She has them because she also struggles a lot with depression). So far nothing has changed, i feel the same shit i felt before. I still want to jump off my window.

Last saturday, my mom went on a week long bussiness trip, so i was left with my grandma. On sunday night/monday morning, i got the very intense urge to cut myself. So i did.

So far ive cut myself 7 times, last one being 2 hours ago. Ive had much time to think about this through, and i think i figured it out. Im cutting myself so i get proper help. Not that "drink more water" "do more exercise" "eat healthier" "talk to people you care about" "just be brave and do it". No, i need help. And the way ive been planning to do that is by collecting evidence. A.k.a my cuts.

By my logic, if my arms look as bad as my mental state, people will finally take me seriously. My plan is, when my mom comes back in 3 days, ill show her my scars and ask for help.

Now, what the hell do i say to her to ask for help?