Writing a minute after GCSE had finsihed

Just to be clear, I did exactly stop writing on time. What I DID do was fill in my details at the top of an extra writing sheet, but the invigilators couldn't necessarily see that and might have thought I was still writing. Nobody said anything to me about it and I don't think it was seen. However, at the end of the exam, I think I saw them pointing to my seat, or at very least the back of the hall near where I was sitting. I suffer from really bad anxiety and am hyperventilating about the consequences. If I was being reported for misconduct, would I be told. Could I be disqualified? Please help, I'm really upset and worried.