After reading the first chapter of the story I was kind of skeptical. It is highly unlikely that anyone would wake up one morning, find they had changed into a bug, and have almost no reaction. Gregor's biggest worry that morning was that he would be late for work. I don't think a manager would personally come to your house if you were an hour late for work. It is also odd that he is still living at home and supporting the whole family by himself.
One word that seemed to resonate to me was "torture." From the very beginning, Gregor woke up changed from a human into a bug. It took him a long time just to try to get out of bed. He was like a baby who has to learn how to do everything from the start. Gregor had to learn how to walk and talk again. Even though he could understand himself when he talked, his family was unable to understand him. Being unable to communicate with others would seem like torture to me. Also, Gregor exerts a tremendous amount of effort in trying to turn the key with his mouth to open the door, and then his father wrestles him right back into the room. This again would seem like torture to me.