clear blue opk smiley face

Simona
I have a question I am on cd 15 first time I will ovulate this late. I did opk since cd10, I tested this morning an I got an empty circle (negative) I tested at 3 pm and got a smiley face, now I have tried again after 4 hrs and got and empty circle again? I do feel ovulation pain, but does this mean my egg is getting ready to be released or has been released already? I am super stressed as i can't bd until tomorrow afternoon and I am extremely scared about missing this month of trying.