upset

We had midterms last week and I haven't received a grade yet for two of my classes. The one I did get a grade for was yesterday in my Concept Design class. I got a B and I'm very upset over that. Let me tell you why. This is a teacher who I like to refer to as "Willy Nilly" because he changes his mind about assignments and how to execute them. Nobody in the class knows what the  hell is going on at any given time, but I think I do well to keep up. I do ask questions, I even go to his office during non-class hours to be sure. We didn't have a midterm test, but we were supposed to show all the work we've done up until now. I had all my work on my flash drive, printed and on the Sdrive at school, so it was no problem to show him everything. I did three designs for three different companies, like we were supposed to do. The girl next to me did only one design and got an A. I asked what I could have done to get an A and it was basically did he like my idea better than hers? No, apparently not. I could have given my designs a bit more, some little thing extra. I understand this, but I feel that I did ALL the work, whereas the girl next to me did some of the work. Is it wrong to think I should have been graded on what we were supposed to do rather than was my design better than someone else's? I was glad the girl next to me did well, but she could tell I was upset about my grade and she agreed about the work part of it. I wonder what kind of grade he gave to people that hardly had anything to show?
So I am off to school today to make more designs from my thumbnail sketches. I'm not sure if this is part of the assignment due or not, I'm just going to do it. I can't get dinged  for doing more, just get a mediocre grade. 
These will be more complex than the previous so I wonder how well I'll do on this one.