How possible is it to get pregnant after just 2 days of having your period

I had sex, about a day or two after my period. And he did cum in me.. Now I feel itty bitty cramps at the bottom of my belly I feel fatter kinda like heavier and my breast (nipples)has been sore for about a week and I'm not supposed to have my next period until August 11-14.  I'm so anxious to know something already...