15 days... You have plenty of revision time. Most physics teachers allow bringing a cheat sheet with you, making memorizing formulas unnecessary, if not, make a 'cheat sheet' consisting of all formulas needed, and then start to commit this to memory.
Armed with your cheat sheet, go through each chapter and do the hardest problems as most teachers use these problems with only a slight twist to them (using past exams is even better if you have access to them).
I usually record the chapter summary and save them to my mp3 player and just listen to them over and over, this will help you ace the general knowledge part of the exam.
When you go to sit the test, I would usually look over the test and make a budget for my time. Then I would start with the big questions and do the initial work, write out formulas and draw a picture of the problem etc. without actually doing the math as this will get you 90% of the marks for only 30% of the time required. Then I would do the rest of the test, and only come back to these problems at the end and work through the math since the actual correct number is only worth 1 mark. If you have time to spare, re-work the math on all problems as you will often miss a point or two over a silly error.
Lastly you can say the students prayer:
"Lord, give me grace on this test, not justice"
Cheers, and good luck!