What going on with my app?

Dominika • 26, happy life in England and amazing kids 😊🎀😍

So I took this two screenshots one minute apart today and it changed my ovulation date, yesterday it said 1 day till ovulation today says it’s 2 days till ovulation. My ovulation tests are negatives. But it’s so confusing now. Is there something wrong with my app?? 🤔