To be very brief: The
error log is not supposed to help you track the individual questions you got wrong, but it's supposed to be a tool you use to analyze what kind of questions you got wrong, identify specific weaknesses, let's say CR EXCEPT questions or quant geometry or the like. Note what questions you got wrong, make a note as to the exact question type, and most importantly make sure you rework the underlying principles of this question type.
Personally, I brush up on the concepts of missed questions each day. My opinion is the sooner you learn that concept the sooner you will stop making that mistake. I will rework those particular question maybe 2 weeks down the line, I want enough time for me to forget the problem and not simply remember the answer, I actually want to have to rethink the problem and for that I need some time in between.
That's how I use my
error log.