The Queen's Diamond Jubilee: The moment a St John cadet, 16, went to read her prayer "I wasn't nervous until David Cameron started reading and I knew that I was coming up and that was then the nerves started building up," she told The Daily Telegraph just moments after the service. When I got up there it was open at this page and because my reading was similar I when I looked closer at it, I realised that it was not mine. I then started flicking trying to find my reading and thankfully I found it and I started reading. Miss Samuel, who is studying GCSE's in French, Law and Public Services at The Misbourne School, Great Missenden, Bucks, added: "When I started reading my prayer I was so relieved, my nerves had gone. I don't know why my reading wasn't there. David Cameron read just before me but I think he had his own reading. I feel so great. It was such an honour to read for the Queen, and Prince Harry. I tried to look at him but he was not looking back. "All my friends keep messaging me saying I was as "cool as a cucumber" and how well I coped with it but I didn't feel like that when I was there." Her father, Kendall, a St John Ambulance Assistant Commissioner (youth) for Buckinghamshire and Milton Keynes, said his daughter composed herself admirably and read with "great aplomb." "She was very nervous and when I realised what had happened my heart just hit the floor," the 49 year-old said. Myself, and anybody else I know, would have crumbled under such pressure. "It is one of those things as a father that you think "am I going to have to get up there and help her" but she is a very strong character and dealt with it so well." He added: "She composed herself, found her page and read absolutely beautifully. I am so proud of her - just bursting with pride. But he said that the slip-up should not have occurred during such a well organised event. He added: "Somebody else should have made it was on her page where she was reading from. It was not her fault. It had not come up during the rehearsal. It was not Mr Cameron's fault. It should have been someone else. The pair were then part of the guests at the Guildhall reception after the service.