You at peninsula medical school? Firstly let me join with you in the rant about how crappy this method of examination is at pms. Secondly i just passed my first year (thankfully) i was achieving low amk scores and just scrapping through but on my last AMK i got quite a high score. My adivce to you is to find out what books other people are using and use them too. Kumar and clark is a must ive heard. What i did to prepare for this exam was that whenever i covered a new topic i revised the clinical info (or as much of it as i could) relevant to that topic. It is also a bit of exam technique you have to bear in mind. Finally your year is quite smart (from what ive heard with the likes of blair??? you'll know him if you were in the exeter locality) . So you shouldnt judge yourself so harshly, end of the day a pass is the pass and your into third year. Things SHOULD be slightly easier in third year seeing as its always clinical. Hop that helps.
Have you considered complaining if it's that bad? What's the pass rate? Not for medical courses specifically, but I've heard it happen where a large percentage of a year failed an exam so they changed the format/questions and let them resit it.