Idk what’s happening


So I’m just confused. I’ve had my period for about 3 years and this has never happened. So I think my period should start soon but like I will go to the bathroom and wipe and there will be dark blood and discharge and then I will think ok it’s time for my period but then I will go to the bathroom again (later in the day) and there will be nothing on the bad and when I wipe there is no sign of bleeding at all. It had been happening for the last three days and I’m really confused. Can someone please help or explain what this could be.😭