Im 17 years old. I lost my virginity on June 30, 2012 w/ out protection & im not on any kind of birth control & never have been. On July 4th i had sexual intercourse again. My last period was June 14 (first day of my last period) & my cycle is 28 days long with that being said my period should have came on July 12th or 13th , but it didn't & im never usually late if so just 2 maybe 3 days .. So i started to worry , i took 4 pregnancy tests , one came out positive the very first one & the rest were negative. I called Pregnancy help center & made an appointment , i went in & the test came out negative. But i was having brown spotting & discharge & kind of light pink aswell .. Then it went away , the next day i was actually bleeding but just when i wiped , my pad only had some spotting , still a bit brown.. Its been 3 weeks since i had sex the first time , & 2 weeks that i had sex july 4th.. Could it still be too early to detect whether i am pregnant or not? Was i just stressing out to much that it caused my period to be late? PLEASE help.