Questions for Sally-anne and Etienne please re distraction

[Wizz29]

My DS sat his 11+ yesterday and during the exam. An older boy he knows, who attends the school already, saw him through the window and they waved to one another -DS does not have a statement but he has ADHD and this "waving" event took his mind of his work for quite a while he says . Naturally I am worried it will affect the outcome and would appreciate any advice - do I need to mention it to anyone now or wait until we get his result? thanks in advance