Jay,
I cannot offer you advice on if you should postpone the exam - only you can make that decision. I can say, however, a 70% score on the simulated exam probably will not work for the actual exam.
There are a number of test-taking strategies on the forum as well on on places like YouTube. Among those strategies are hints on how to read the question, marking long-worded questions to come back to later and the like. The hints that worked best for me were:
1. Understand the general question types: Short questions, 3+ sentence questions, scenario questions, formula-based questions and ITTO questions.
2. Read the last sentence of the question first and read it very carefully then read the answers: Find out what the question is asking. (In many instances, all of the information above the real question is "fluff." Look for keywords like "most likely," "least likely," "best" and so forth. You may be able to eliminate answers fairly quickly.
3. Be careful of questions that have "best course of action" and "first thing to do" types. Remember to answer from the perspective of PMI or the PMBOK Guide - not what you would personally do.
4. Know the formulas and use the correct one.
With respect to ITTOs - I did not memorize the ITTOs for every process. Many processes share ITTOs - I learned the unique ones for each process.
Good luck!
Harry
+++++
Harry J. Elston, Ph.D., CIH, PMP