Submitted 10 out of 100 question midterm on accident. What do I do?!?!?!?

So I just had a bit of a crisis, and I am completely panicking right now. I just submitted 10 out of 100 questions for the midterm BY MISTAKE. I umed there was only 10 questions and left all the rest of the questions were left unanswered. My grade has dropped from a 82% to a 50% and when I saw that I almost bursted to tears!! I emailed my professor, but I'm not sure what he's going to say. What do you think he will say?????