Then the best course of action is to grab a typical 1st Yr uni "Calculus" textbook; there'll be enough to keep you busy until you get to uni. There are dozens of current US Calculus textbooks - all so beautifully set out, with outstanding graphics, etc - quite unlike the books I used to use. These textbooks, new, cost over $100 each; but on 8 - 9th October, next month, there will be a giant Lifeline Book Sale at Oakhill College, Castle Hill (8am to 5 pm), where, if you are lucky, you may be able to pick up one of such 2nd-hand textbooks for less than $10(be really early). I remember picking up a few for just $2 to $5! Even if the textbook is over 10 years old, it's still great.
ps
Also grab an introductory text on Linear Algebra, and on Discrete Maths. That should cover a huge chunk of you 1st Yr uni maths. You may just be lucky and find such books at the said Book Sale.