the first working day

After finding looking for a job in for a long time, I just got a job in the accounting department at a global company. I don't know why I feel so more nervous more than happy. Maybe I am not confident enough to be in charge of this position or there's another reason that I haven't discovered. Before I arrived at the company, I thought that I was chosen because they judged my abilities in the interview. All of thing don't right to me. I don't understand what the last sentence means. My best guess: Nothing seems right to me.