Curious if ovulation could of happend

I.had my positive opk strip and digital on the 15th and 16th and then after the 2 days i retested lines were light and cb advanced opk was neg. Well i have been feeling a lil cramping like af kinda and so i decided to take an opk again and lines are dark and cb digital is a blinking smiley what could this mean also.i.was.only able to have sex on sat.sun mon. Early morning on monday and i.was supposed.to.ovulate on the 17th i believe so what do you all think?? Did i ovulate or am i about too also today i had eggwhite cm