EARLY OVULATION!!!!

Hey ladies, so I have started using these prenatals in April, I usually start testing around cycle day 11 because I ovulate on cycle day 15 or 16 like clock work. So April since I know when I ovulate I usually start test on CD 13, ok so I tested and it was faint, which means negative right? Ok then, tested again on CD 14 negative, 15 negative 16 negative. I was like “ did this damn pills push back my ovulation”? I tested until 3 days before my period came. Anyway I didn’t want to stop taking it because I wanted to see if it would happen again next cycle. I started testing on CD 5 soon after my period ended, low and behold I got a peak on CD9!!! on CD9 yo. I didn’t have sex on the days I was supposed to because I really didn’t think I would ovulate that soon. Now this month same thing! So my question is, has anyone ever taken these and started ovulating early??? Sorry for the long post