I've heard a friend had this test before and the report showed abnormal also. But she then went for more detailed test and found everything's alright. Then she asked the doctor why, and the doctor told her this test is for reference only and not an accurate test.
Although both of kwokwpy and I said the idex is not trustable, I still want you to go see doctor for safety sake. Then your queries will be all solved.
But I suggest to go another doctor for a more fair comment.