Ovulation

Hi I'm new here but had a question. Since I had my son 2 years ago I have been very very regular and my ovulation is quite noticeable. I feel it the day before have the sticky discharge and in a lot of pain the day of. But this month I felt nothing. Now I'm about to start and have been feeling a little pinching on my left side but nothing that compares to how ovulation feels for me. What gives? I'm healthy, active, and only 24.