Trigger shot after ovulation?

Haiii guys, wanted to clarify about taking beta hcg after ovulation. Yesterday when I did the scanning my follicle was 19.2mm and it was ready for rupture according to my radiologist. After that I contacted my gynec Bt couldn’t get in touch till 9pm. She said I can take a trigger shot today morning. Bt yesterday night I had severe lower abdominal and lower back pain. Today my opk test line has faded when compared to yesterday. So does that mean I have already ovulated. Then should I take the trigger shot? Anyone has any idea? I am posting the opk result pics here. The darker one is of CD 18 and the lighter one was taken now(CD 19)