Ok. Breath. Find out how the rest of your class did. It always does help to determine if perhaps the professor was unnecessarily hard when writing their exams/tests, and perhaps that would be shown in what your other classmates got in the class as well.

You did well, anything beyond a 70% is considered a "solid grade" even if it's not as high as you'd like it to be. I'd suggest that you talk to an academic advisor, and if it's advised - you could always retake the class to earn a higher grade if you so desire.