My 4th road test is coming up, I can't sleep and I want to harm myself

I started learning in November with overall average performance, had my first test in march which I almost passed and got my hopes up. the last 2 attempts were horrific, I'm not even making any mistakes, I just get nervous and scared and ignore instructions. for the last couple of days I cry myself to sleep for several hours and my chest hurts everytime I think about it, and it's gonna be like that until I inevitably fail again. I'm so ashamed of myself because my poor father is working so hard to pay for all of this and it just doesn't matter no matter how hard I try. I really want to punish myself somehow and I don't really want to go into detail about what I do to myself but it obviously isn't healthy. I just don't know what to do anymore, I know a couple of people who are 60 years old or more and they passed their tests, I'm so young and smart and yet I can't do this no matter what I do, it makes me feel so small and worthless