Does Mood Swings And Mild Cramping Indicate Sign Of Pregnancy?

The 1st and 8th of March I had sex...my period is due the 13th according to my tracker. When I had sex the 8th I bled alot but it stopped and turned brown. I have been severely Moody and have been having mild cramping I am assuming due to constipation...I have been tired also and have the need to go to the bathroom frequently. I wonder if there is a possibility I maybe pregnant.