Okay help!!!! Ovulation strips

So I have been taking ovulation tests for three days 
Cd16 afternoon above
Cd16 morning urine above
Cd15 afternoon above
Cd14 afternoon above 
As you can see it gets darker but not a full positive test this morning cd16 morning urine and now this afternoon line is so faint again
When do you think I ovulated? 
Had sex cd 15 pm and a bunch of times before that. But that time was the closest to that window
If I had a kind of positive this morning maybe it was really positive last night? And I will ovulate within 24-36 hours from last night? And the sex last night would be in that window?
Opinions needed!!!! And how soon can I test?