老师们好！

Diana Herbert was running late for school on Friday morning so she decided to take a shortcut. Little did 16-year-old Herbert know this would make a big difference in her life.

While Herbert was walking fast to try to get to school on time, an elderly gentleman stopped her, and asked Herbert to tie his shoelaces for him. At first she was a bit hesitant but then she saw that the old man was unable to use his hands properly and had a walking stick. She realized that he could not really help himself so she bent down to do that for him. After she finished tying the man's lace, the man thanked Herbert. Then she continued on her way to school, hardly thinking of the situation.

What Herbert did not know is that a woman named Nadine Ribeiro witnessed the whole thing. Ribeiro stopped her car and took a photo. She then posted it on her Facebook and wrote about the situation. Unexpectedly,

the photograph on the social media spread quickly - more than 3,000 people liked Ribeiro’s photograph while 6,000 more shared it with their friends.

Herbert, however, did not know what was going on until the principal told her that she became some kind of internet superstar.

Herbert said she couldn’t understand why people were so attracted by the act.

The following Monday, Herbert was honored by the school for her kindness.

“I was not expecting that much attention, but it felt nice to get recognition for something good,” Herbert said. “I believe in karma - once we do nice things it will in some way benefit us in return.

为什么用了过去进行时was not expecting, 却又用了一般过去时felt呢？

是否2个也都可以用一般过去时，或2个都用过去进行时呢？如何真正理解文章中的时态含义呢？麻烦老师深度分析，谢谢。