CPE enquiry

Hello,
I have just got my CPE results and...what a sad surpsise! I got C, just two marks away from B... Actually, I have been expecting A or B. Does it make sense then to ask for marking process repetition? May that change the mark from C to B? Does anyone have expereince with that? more or less, the issue concerns writing. I thought it would be really good. And it is only Borderline-Good.