If you keep going in the direction you are headed then you will get there!
If you are looking for extra support for your learning and assessment for NCEA Maths, Science and English try this site! http://www.studyit.org.nz/
Choose your subject and then the standards you need support for. There is lots of expert advice especially for external standards.
NB: Year 13 this site does not yet have the new Level 3 standards