السلام عليكم و رحمة الله و بركاتهA person once arranged a session with a teacher for a fixed time period. When the time period (almost) ended, the student said, this is the last question.Even after that, he asked one more question to the teacher. The student thinks the teacher was annoyed by this.Was the student sinful?Is the student suppose to give more money to the teacher because of this?

All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.

If the student did not intend to lie, then there is no sin on him and he is not obliged to pay anything extra to the teacher.

From looking into the history log of your questions, we noticed that you ask too many questions. Therefore, we draw your attention that asking too many detailed questions is a dispraised matter in Islam. Abu Hurayrah narrated that the Messenger of Allah said: "Do not ask me so long as I do not impose anything upon you, because those who were before you were destroyed on account of their frequent questioning and their disagreement with their Prophets. Therefore, when I order you to do something, do it as far as you can; and when I forbid you from doing anything, eschew it." [Muslim]

Allah knows best.