Uthup,
You claim to be an immigration agent. Your answer should be more specific. You cannot score less and then "think Positive". Meena, I dont understand why you dont have time. sure 67 is enough to qualify you, but it doesnt harm to have atleast 2 more points extra. You asked advise, every one gave you the advise, and now you want every one to prove why you should write the test again? It is entirely your call, but immigration is a life changing matter, better safe then sorry.