Pregnacy ? Help

My boyfriend came in me during day 2-3 of my period & my periods only run 4 or 5 days . This is the only time he came in me to both our knowledge. My period was due on the 13th of this month & it is not the 18th and still hasnt come ... I took a pregnancy test on the 14th & it was negative , no faded line it was dark negative ! But i have been having pregnancy symptoms... Peeing ALOT ALOT ALOT & Sleeping ALOT ALOT ALOT .. uncontrollably tired . But maybe that is my period coming on ? idk ! Has anyone else ever got pregnant on there period ? I AM NOT FERTILE AT ALL SO DIDNT THINK IT WOULD OR COULD HAPPEN .. plus the test was negative ?