18 years old. Wasted potential? I'm scared.

I'm scared. I've struggled A LOT with mental health and I still am. I'm trying so hard everyday and no one knows how much I do. I've been told my whole life that I'm smart and intelligent BY EVERY SINGLE TEACHER I've ever had and MY PARENTS AS WELL but somehow I can never live up to my potential.

I keep failing every exam. I feel like I'm doing a disservice to myself and I live in constant guilt.

I have an entrance exam coming up in 5 months and it's my chance to get into my dream college. Everyone has really high expectations from me. I'm scared I won't make it.
I'm scared I'm going to be sad forever.