hello I had my period last 11th of sept. I had sex w/my bf last Sept 24-29 ... I had again my period on 30th with headaches, cramps, backpains.. it laster for 5days...a week aftr my period I again experiecend strong headache and I got sick.. like flu.. and just this night I had slight cramps backache and when I went to wee, I saw a slight blood on my undies. what could it be? I'm worried.. could I be Preggy?