the last period i got was in july i had unprotected sex and used the withdrawl method around the 8th and 13th of august its now the 5th of september i took a hpt yesterday morning (first response early result) and it had a faint very faint positive line and i took one today and 600 pm and nothing , negitive, im very confused im 16 so far i get light headed when i stand up for about 5 seconds and my bowls have changed oh yeah and on the 16-20 of aug. i had a EXTREMLY light bleeding it was light pink four day and brownish one day...no itching or burning ..........any advise