Do I Need to Be Shouted At - What warrants her to shout at me?

After the School Examination, the school has arranged activities for the students. One of the Activities was to Dragon Kiln for pottery making.

According to the bus schedule given to by the teacher/s-in-charge was to return at 13:15hrs. I certainly book the bus according to the schedule that was given to me in black and white.

However on the day of event there was a change and the activity ended earlier and the teacher-in-charge called me on my cellphone to arrange for earlier pickup time. As it was a last minute arrangement the bus company agreed to help out. The teacher-in-charge was inform that the arrangement by the bus company.

Since I have informed the teacher-in-charge that the bus company will do their best to get the buses there as soon as possible but no promises. The teacher-in-charge has informed the Ms SP. She called the teacher-in-charge for my mobile and questioned me during my lunch why was her transport late. According to the schedule given to me the bus should be there at 13:15hr and not earlier and it is by goodwill that they bus is there early.

2) I said "hello - didnt the teacher-in-charge informed you of the arrangment?
3) She deems that by using the word "hello" is being rude to her.
4) If the word is "hello" is rude when why would it be used a greeting? English teacher please explain.
5) Who is she is reprimand me? What is the cause of it?

My analysis of 5.

1) She is either frustrated and unable to cope as a teacher. Which is in another word imcompetency.
2) She thinks that a teacher she has every right to shout and condemn others ability without questioning her ability.
3) The insitution must been week in selection of personnel in doing the necessary job.
4) Her behaviour is the reputation of the organization and also the industry.
5) Even the prime minister, mps, prinicpal and vice principal do not shout at others - why because they know they are in control.
6) Her behaviour has indicated that she is out of control at the site and therefore lost her cool and shouted at other. ha ha ha

Thank you for reading.