I cleared my exam recently. I think you shouldn't be worrying about your percentage. However should be taking time to read the rationales of each question will help you to understand and answer higher level questions. Memorizing only help you to answer direct questions and that's all lower level questions. When it comes to answer application question we have to have some idea bout the content. I would recommend reading Sunders( That's what I did) and marking the difficult questions in Uworld and wrong ones and do it again. Sent me your email. I will sent you a cartoon explanation of each disease condition and its s/s. It will help you to understand better.