going against the general flow of advice but definitely email your exams officer! Tell him what happened in writing, and then depending on what he says call Edexcel too. Better to be safe than sorry!
Just read that she wasn't responding ; it's up to you. Ring your main school/go in and talk to exams officer. If you really are that panicked, tell a more senior teacher if you cant find exams officer. Don't let other people tell you you're being silly; this is important for you! I'm sure it's fine; they do check it, but if it's nagging you then ask!