I understand how you feel after the recent exam mishap. Overlooking the textbook in an open book exam is a mistake many could make under stress. Remember, one exam doesn't define your entire academic journey. Consider this a learning opportunity for future exams. It's also a good idea to talk to your instructor about your concerns; they might offer some insights or solutions. In the past I have had the opportunity to re-do coursework, so your academic team will be able to advise what is possible for you. Meanwhile, focus on upcoming assignments or exams to balance out this experience. Remember, everyone makes mistakes, and it's how we grow from them that matters. Stay positive and don't be too hard on yourself.