SHE first said that being in the same class as senpai is gross, and after the scores "DO YOU HATE THE IDEA OF BEING IN THE SAME CLASS AS ME THAT MUCH?" What type of logic is this?? Maybe a high school girl in love.. xD
She was definitely happy about him wanting to be in the same class as her and she yelled at him to cover up her embarrassment. Then she was disappointed when he passed the exam. There was no contradiction.