All that i planned, now met with a huge obstacle

Got my final year results. I was surprised i didn't clear one subject. Really stunned. Why was i not given a subsidary pass??. My attendance was ok, my conduct was good. I even attend the practical lessons and did my practical without my partner. And i never failed my practical, why was i not considered for a subsidary pass? Why Mrs. Kwan? Did i ever give you any trouble? I don't think so. Even if i really failed the paper surely you help me a bit by considering my practical lessons. This is about my future. I wanted to go into a polytechnic. And with this the chances of me entering is really slim. I cannot just apply for ITE again and retook everything. This is my 2nd chance to enter poly. I've already wasted my 1st chance that is after 'O' Levels. I did really badly for it. All i managed to get into was ITE. And that was NTC-2. Why???? Can someone please tell me what am i suppose to do?? I've got a temp job at ITE Yishun now as Teaching Asst. But i need to take my failed module again. How??

*migraine is killing me, end this trauma please*