Thanks all for your tips and reassurance.
My son completed a VR NFER paper last night, within the time limit, with a score of 91% !!!!!!!!!!. I have told him, I am really proud of him. He has also just earned a place in his football team, as sub goalie, which is a major achievement for him.
The problem I have, is that the NFER practice tests are 85 questions in 50 mins, however the real test is 100 questions, so what he has been practicing ,will have to be stepped up on if he is to complete the actual test in the time allowed.
I have decided not to push any harder with my son. He is currently practicing his tecnique using the Susan Daughtry extra practice book, which will help his speed. If he has this problem, then I am sure there are others taking the test, that have this problem too. At the moment he is feeling very confident, which is new to him and the most important thing to take into the test.
As you have all pointed out, as long as he tries his best, who could ask for any more. I will be very proud of him and the commitment he has shown over the past few months, whatever the outcome.