thanks again for all the replies guys begining to feel a little better now...
in response to the question no they didnt tell me on the day and still havent as i havent failed the medical they just need to look a little more into it (did they make you run round the car park)!?
working out a lot more now and have a breathing trainer device. initially was only 4% below the pass so hopefully retest will be a pass.
In relation to lung size my bupa specialist too said that the result i blew for him was representative of very healthy lungs, i just have bigger lungs than norm. hopefully this will persuade them
Thanks again