Well, a day could be considered terrible in a short story if there's a major disaster, like a natural calamity that destroys everything. Or it could be a personal tragedy, like the death of a loved one.
It was a terrible day. I had planned a picnic with my friends. I prepared all the food the night before. But when we got to the park, it started to rain heavily. We tried to find shelter under a big tree, but it was still wet and uncomfortable. Then, one of my friends got a call that she had an emergency at home. So we had to pack up and leave. I was left with all the uneaten food and a sense of disappointment.
Well, it all started when I found out I lost my wallet as soon as I left home. I retraced my steps but couldn't find it. So, I had no money for the bus and had to walk to school. On the way, it started to rain heavily and I got soaked. Once at school, I realized I had left my homework at home. That day was full of mishaps and was just terrible.
Maybe someone loses their job on a terrible day. They could be called into the boss's office unexpectedly and be told that they are no longer needed due to budget cuts or some other reason. It would be a huge shock and make the day extremely bad.
I had a terrible day at work last week. I woke up late and rushed to the office. As soon as I got there, my boss scolded me for being late. Then, I found out that I had made a big mistake in an important report. I had to spend the whole day correcting it. And on top of that, the coffee machine was broken, so I couldn't have my favorite coffee to keep me going. It was really a nightmare of a day.
Maybe you get stuck in traffic on the way to work and are late. Then you find out you've missed an important email. During the day, you could accidentally break some office equipment.
Sure. I got to work late because my alarm didn't go off. Then I spilled coffee on my important papers right before a big meeting. During the meeting, I couldn't find the report I was supposed to present and made a fool of myself in front of the boss. It was just one disaster after another.
One common element is unexpected bad events. For example, like getting a flat tire on your way to an important place. Another is a series of misfortunes. Maybe you spill something on your clothes and then miss the bus right after. Also, things not going as planned, such as a party being cancelled last - minute due to unforeseen circumstances.
Well, here is a story. I planned a lovely picnic with my friends. But in the morning, it started to rain heavily. All the food I prepared got wet. And then I realized I left my phone at home so I couldn't call my friends to cancel. I just sat there in the rain, feeling so miserable. That was such a terrible day.