What Causes Fatigue And Anxiety During Menstrual Periods?

I have just started a period which was a week late but i feel very tired, my skin is very bad and i am extremely anxious all the time. None of these things are very common for me as i have a coil fitted so my period tend to be like clockwork (although they are quite heavy) and i do get the occasional blemish but nothing like this. would there be any underlying reason for any of these things or is it just coincidence??