studied hard but fail, band 7

I studied (Schweser notes and solved questions from the CFAI books ) hard and repeated the material 4 times, I didnt understand the questions related to Quantitative, Portfolio, Alternative and others. I was sick before the exam and I stressed to hell but not sure if it effected my ability. On the exam I found the questions on the second part of each test are unfamiliar and couldnt answer them.