When I was 20, I felt bad about myself

Still know that you should not think negatively but why every night my tears fall, suppressing all the criticisms that my heart aches. At the age of 20, I am as old as 25, thinking like a 10-year-old child.

I do work slowly and awkwardly, work as a worker who is reprimanded by the group leader, who is also scolded for going to a restaurant.

I always told myself to try hard, this method didn't work, then changed to another method. Why am I forever a bad person. I don't know why I am slow to understand, crash something, the simple thing I messed up. I could not do the job, people sympathized for me time and time again and again. What should I do?