Impending doom

Dear Pupu

I had an uneasy feeling yesterday. Sometimes my hands can start shivering when I'm not cold at all. I couldn't even sleep well at night. I kept having a sense of fear, a sense of impending doom. Then today I just realized something catastrophic. I made another fatal mistake in my first paper that will cause a series of chain reactions! I am overwhelmed with grief.

What's the point of studying so hard when careless mistakes can ruin everything?