When did I ovulate?

Yesterday I had EWCM, opk was getting darker but not quite there. This morning was the darkest it has been, I've had watery CM but no longer EWCM. took another test this evening and its lighter again. Does this mean ovulation has already come and gone? Trying to decide if I actually ovulated yesterday or today.....Would the line get lighter once you've already ovulated? I've heard you actually ovulate the day AFTER a positive opk though so I am very confused. Pics below of my darkest line, then the one 10 hours later that is lighter