I got caught cheating on a Japanese quiz?

I know it's really bad to cheat, but hear me out.
The finals have began and I'm sick.
I had my 7th period final today and our schedule was backwards.
When I went into my Japanese class (not what I had a final on).
We had a quiz on vocab.
I used my iPhone and was caught for cheating.
She told me that she was going to have to tell the Dean and the dean was most likely to tell my parents, probably my mom.
I only cheated because I have a C in that class, and my mom was stressing about raising it. (It's my lowest grade)
I'm so scared because my mom already told me last night that she'd take all my electronics away if I didn't raise the grade.
CAN YOU IMAGINE HOW SHE'D REACT?!
I'm probably going to get abused.
I've been crying, stressing, and feeling guilty about it.
I'm positive this will show up on my record.

I know, don't cheat again and it's bad.

BUT DO I TELL MY MOM MYSELF OR LET THE SCHOOL CONTACT HER?
Also when I was first caught, I tried to the deny it, then eventually gave up. Will that hurt the punishment more?
Will colleges see this?
I'm a freshmen in high school.

My mom is going to kill me

I don't get why everyone else didn't get caught.

Maybe nobody else got caught because they * weren't doing it *!

Man up, accept what you did, and be honest. Explain why.