I don't think you should remark it because 9 marks is quite big, however if you feel the exams went differently to your results, you should. Are you taking a gap year? In this case, if you need it for uni, I recommend you should resit, but if you need a C, it's fine.
I'm kind of in the same boat, I was 4 marks away from an A in sociology and 2 marks away from an A in psychology too. Really unsure on whether remarking is worth it. I'm taking a gap year tho, so I could also resit psychology and get an A* bc that B was so surprising to me.