Particle physics is normally taken in the last year or two or undegrad. You have a long way to go. By the way, I would like to know why you say:
I started year 11 physics a couple of weeks ago and I have found that none of it holds my interest nearly as much as particle/nuclear physics.
I very much doubt that you know anything about particle physics, unless you have read about it in popular science books, which give you a very bad idea about what physics is really like. Those books are written with the aim of selling many copies, not informing the reader.
I don't know why people always say classical physics (what you should be learning in physics now) is boring. Many generations of brilliant physicist were intensely interested in classical physics. Einstein's love of classical physics led him to his discovery of relativity.
You should first learn your school physics. Then before you get to particle physics you should learn the following physics at the very least: calculus-based mechanics and electromagnetism; intermediate mechanics (Lagrangian methods) and electromagnetism (at the level of Griffiths); quantum mechanics (at the level of Griffiths). And also the following math: single- and multi-variable calculus; linear algebra; differential equations; complex analysis.
As you can see it is a long way to go before you can start studying particle physics. My suggestion is to see if you really have an interest in physics or not, and not to worry about particle physics until much later. Here are some books you should read to gauge whether you actually love physics or not:
The Character of Physical Law by Feynman. (No math at all)
http://en.wikipedia.org/wiki/The_Feynman_Lectures_on_Physics" by Feynman.
Physics by Halliday and Resnick. (a calculus-based textbook)
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