I have taken pregnancy test for a little over a week, like every couple of days, and the second line showed up so faint that the only way you can see it is in bright light, and it shows up in the time frame, what could that mean?

Either early or fals: Home tests, when positive, should be very clear. I admire you for making sure of the time - that's a very common mistake. Your best bet is to contact your obgyn and get a blood pregnant test - they are more sensitive and will give you your answer. Good luck and start taking prenatal vitamins now.

Difficult to say: Based on the history you provided, you do not say if your are testing before or after your expected menses. It could be early pregnancy and too early to tell. It could be a nonviable pregnancy. It could be a false positive test. Please follow-up with your OB clinician if you are concerned you may be pregnant.