Help!!!! +Opk/day one of period

Hey everyone I have been using the cleablue advanced digital test it has blank smiley, flashing smiley, or solid. For the past week I've had flashing smiley face prior to that I only had the empty smiley. I never got a solid smiley face. Well today is day one of my period and I'm still getting a flashing smiley face even tonight. Has anyone had this happen before and why??!?!? Or has anyone heard of why this would happen and what causes it. I'm so confused I thought it would go back to empty being on period???

Thank you!!