Hello Violinist,
Firstly don't beat yourself up about it...you plainly have very set goals but to use your own point are you missing out on the fun getting there by just exam bashing...I am glad that you don't just learn the three pieces and do lots of different repetoire thats very important...sometimes its important to remember why we play...we play because we have something to communicate...music is our language, without it we are in a way mute....
I don't know of you play in any ensembles but that can be a great way to take oneself out of the exam loop and have some fun whilst learning at the same time...Music isn't all about exams its about life, beauty and the human spirit, exams are purely markers along that road to self expression to guage how we are doing and to give others an idea of our standard of musical achivement.
Go out and have some fun with your music...play some old repetoire and see how much you have improved, be your own examiner for awhile and enjoy it...be honest about your performance and enjoy Enjoy ENJOY, have a giggle at your mistakes, they too are all part of learning and will help you when you teach someone else..who will no doubt make the very same mistakes as we all did...
Remeber music is an Art not a science...music comes from the mind and soul of both the composer and the artist playing it, I doubt any technology could manage that...it may have the power intelligence wise but it cannot empathise, it does not have the living spark...
So get your violin out and play, play in the garden, play on the heath, in a field astound others with what you can do...my neighbours often comment "oooh that was lovely" (obvviously very discerning music lovers

)
All the best...keep your fiddle up...you will achieve what you want to but have some fun getting there...
Andrew