The professor will get chewed out for this. My students were taking a midterm when the tornado siren went off. After taking them to a safe location I gave them the option to continue working. I simply didn’t have a plan for what to do in that situation so that’s what I came up with. After it was all over I put up a makeup exam on our classroom management software to give everyone a chance to redo the exam. I thought I was being fair. Someone reported me for violating the rule that “all classroom activity should end when the siren goes off” and the head of my department had a very stern talk with me where he strongly implied this was something I could get fired over. At the end of the conversation he said “well, I hope you learned your lesson, not that this is ever going to happen again”. Oof. That’s all to say that your profs are people too and that they don’t always make the right decision in the heat of the moment. You and your classmates should reach out and let him/her know that you’d like a chance to retake the exam given the circumstances. Don’t be dicks about it, but give the prof a chance to make things right. I’m sorry you went through such a stressful event.