Period acting weird

So my period normally last 5 to 6 days and is always heavy first 2 to 3 days i have to change my cup almost every 2 hours and the last days every 4 to 6 hours its always a normal looking color with some clotting. But this month my period lasted like maybe 4 days super light i maybe changed my cup twice a day on the first 2 days and then once the last days. It was super dark i don't remember seeing any blood clots and it seemed to have a mucus texture. I have also be super tired. I was wondering if anyone else experienced the sam thing or had any idea of why this happened