Thanks for all of the replies!
I am 20 years old, 12 stone and a non-smoker RatherBeFlying.
I doubt your pulse was really 42 even if you are training for the olympics so I suspect ALL the readings were inaccurate. The diastolic is the one that doctors worry about (ok chaps lets not restart that thread) and yours is fine. Dont forget your blood pressure was checked for your class 2 and must have been OK!!!
....For anyone else wanting to self worry, so called cheap machines are fine but they need to be made by a reputable company. Omron is my recommendation
The machine in question was an Omron! And my heart rate is indeed that slow (confirmed with multiple HRM I own! I am very active!
Again thank you for all the help! I think I'll be fine, will just have to relax at the medical and fingers crossed it wont be a problem!