Cramps but not menstrual cramps???

Marianna
My period was supposed to come on the 16th of this month. I've noticed very light spotting but nothing heavy since then. Now I've been experiencing mild cramps in my lower abdomen area. 
Picture one shows when I stopped my period and when I began ovulating and when my husband and myself had sex
Second picture shows when I'm in the fertile stage in my cycle and once when my husband and myself had sex and when my period is supposed to be due