To the best of my knowledge, the GP makes notes whenever you visit, even the minor things; I suppose that, if you go in with, say, sneezing at certain times of the year, he/she can look back over your visits and work out that you might have hay fever because it happens at specific times. That's just an off the cuff example. I'm not medically qualified, though. Look out for a better response from someone who is.
If I may ask - is there something you have visited the GP about and which you are worried will cause problems with an application to join the Royal Navy?
The RN is not overly worried about drugs problems is the past as long as they are in the past. You are liable to drugs testing once in the RN, if you are caught then you will be thrown out. When you have you medical with the AFCO Medical Examiner they will ask you about your previous medical record and only if they are worried about anything mentioned will they contact your Dr for clarification.
So I wouldn't worry about it too much provided that you have learnt your lesson.
thank you supermario for that im completely against drugs now anyway i found it was just the social circle i was in at the time ive never had any previous medical conditions so hopefully everything will be ok was just worried because im putting everything in to this at the momment going to the gym everyday and doing alot of research just didnt want something stupid to spoil it
It is worth noting that you are entitled to look at your medical records. You must book an appointment with your GP, and let them know beforehand that you wish to see your records during that appointment. There are only a very limited number of things that they can legally not let you see, and only if you are, for want of a better description, mentally unstable or potentially so.