i need some insight!

okay so my period ended 4-26-15 i think i ovulated right after my period...me and my husband had sex the 27,28,29,may1st &2nd...and now today i have light spotting which is light pinkish no cramps no strange symptoms just that been a little tired and dizzy lately not expecting next period until may 23...also my periods are always normal i havent been trying to conceive for awhile but this the first time this has ever happened...any ideas ??