If two faint lines appeared within the first 10 minutes of taking the test, then it usually means pregnancy. If you are seeing super faint lines after those 10 minutes are up, they could be evaporation lines. The lines that appear must appear within the first 10 minutes. If you just missed your period, it is possible that you do not have enough of the testing hormone in your system yet. If that is the case, then you should wait a few more days and test again.