3 days positive on ovulation test

Emma • 💖10/12 💙06/15 👶 04/18
I've only been doing the ovulation test for 2 months so I'm still learning. I've had positive ones since the 27th. So naturally we've done it everyday just to be safe but I don't understand why because I though it should only be for 2 at most? What's the reasoning here and is it normal?