scared to have low grades

Everytime I hear about Periodical test I always think if our test is easy or not. Because I want to have an high grades so that my parents will be happy of me. Everynight I always review all the things we taken in third grading lessons. Eventhough im so tired, I push my self to have review because I do not want to have low grades. When our test has come I always pray that I will not be confused or panic so that I can concentrate the test. Everything is easy if I review harder but im too lazy to have an review. My grades in other subject are low but in other is high. I promise this last Periodical test all I can give is more effort. I want to graduate this coming Aprilso that I strive harder this last EXAM.