/ need advice and contacts
Do you have local climbing club or mountaineering club?
Your first port of call, as someone has already said, will be to look into local climbing clubs ( not all take under 18s though ). If there is a local climbing wall near you go there to learn and practice and also make contacts - many walls have a noticeboard to help people meet up.
You could consider a climbing course - I went to Plas Y Brenin for a rock climbing course when I was 16 and learned loads from it. Check out the Conville course ( I supsect it is for over 18s ).
The British Schools Exploring Society used to run expeditions. You might also consider Ten Tors, if you are not too far from the Southwest, or D. of E. Both of these will set you up for some good skills required in mountaineering.
It sounds like you've got off to a flying start and congratulations on your achievements so far. You've certainly got high ambitions and with perseverance, skills and commitment you'll be on the road to making your dreams a reality. Recognising, and making the most of opportunities is undoubtedly going to be crucial for you.
The others have already made some great suggestions and I definitely agree that getting some training and experience with a professional mountaineer would be ideal for you. One person you could get in touch with is Tim Mosedale. He's based in Keswick but runs expeditions on Everest and other high mountains. His website is: http://www.timmosedale.co.uk/ You can also read an interview by him here: http://adventure-eyes.co.uk/wp-content/uploads/2012/03/Downloadable-Version-of-the-Adventure-Eyes-In... As I say, it may be worth an email...
Good luck with making it happen for yourself!
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