I'm 19 years old i've been sexually active for about 2 year now i did have unprotected sex with my boy friend and then about a week later I started bleeding but not heavy at all i thought it could be an early period so i used a tampon this accrued for two days then it stopped and i started to have terrible cramps in my lower stomach i have been having an unusual amount of clear odorless dis charge.and occasional spotting this has been going on for about 4 days i also took a pt and it was negative but i did take it late in the day and i have not been late on my period yet i'm still waiting to start my period i usually get it at the very end of the month could i be pregnant, have a yeast infection, or an std i have never been tested before but also have never had any problems till now i have no health insurance so i'm trying to get some answers any was possible also kinda dirty but i've been gassy to!!