Early Pregnancy Symptoms & Period Confusion: What to Know

Question
is there a possibility that i might be pregnant and my body doesn't know it yet?possibly because it's so close to my period.i am haveing light spotting and the pregnancy test is starting to show up possitive.and why would the pregnancy test show up possitive at all,if i am not pregnant?
Followup To
Question -
i took a pregnancy test yesterday and it had a faint positive sign and then i started my period later that evening.could i be pregnant and my body just doesn't know it yet?it is a very light period probably triggered by intercourse.what do you think?and my husband and i have been trying to get pregnant for about 6 months when should we consider in vitro?and how much does it cost?
Answer -
The manufacturers claim that, in order for a pregnancy test to be considered positive, the lines have to be dark and bold. Any faint line must be read as a negative test. The best time to take a pregnancy test is seven days after missing a period. If you believe that you may be pregnant, wait an additional seven days and repeat the test. If it is still negative, you are not pregnant.  Usually, if you have a normal 28 day cycle (from the first day of your period until the first day of your next period) ovulation occurs on cycle day #14. You can only become pregnant if you have unprotected sex on cycle day #13, 14, 15, or 16 each month. Concentrate on having sex on those days each month. If, after trying consistently for 12 months, you still have not conceived, then it is time to consult a gynecologist. You may need help with ovulation, which may merely be started using Clomid. It is far too early to start considering in-vitro fertilization.  

Answer
Most pregnancy tests have a "threshhold" below which a negative result is found. A pregnancy test usually will not show a positive result until 14-21 days after conception. However, some pregnancy tests are more sensitive than others. As I mentioned before, the manufacturers claim that one cannot consider a test positive unless the lines are bold and dark. A faint positive must be considered to be a negative test. If, of course, you have any doubts, repeat the test or take a blood test for pregnancy (Beta HCG) which is a bit more accurate. All pregnancy tests test for the presence of human chorionic gonadotropic hormone (HCG). If it is present, you are pregnant. If it is absent you are not pregnant. HOwever, in order for the test to be positive, a threshhold must be reached. That is why we suggest that the best time to take the pregnancy test is seven days after missing your period.