My last period started on August 8th...I was supposed to start my period last Wednesday (September 14) I still haven't started and took a pregnant test on Friday that was negative and one on Saturday that was negative...I have no feelings or signs of my period coming but extremely tired, have terrible headaches in the afternoon and slight cramping/tightening in the lower abdomend (not like period cramps though)...should I test again...could I be pregnant? We have been trying for 3 months...