pregnant?

On the 16 me and boyfriend had unprotected sex and my period started that next day then on the 20 (end of period) we did the same also on the 25 and 26 it's been 1 week and a few days since the first time and I have cramps nausea and I am SUPER tired also just realized when my nipples get hard the areola shrivels up that could be knew or old I never paid attention. I know it's not all in my head because I Know my body and I have had pregnancy scares before. how early can you start getting symptoms? plus my ovulation week starts in 2 days.