What Causes Heavy Menstrual Period With Expulsion Of Mirena Coil?

HI, I have has a mirena coil fitted about 7 months or so ago. I have always had heavy periods and been anaemic. Since it was fitted my periods have still been heavy. At the start of my last period i noticed something in the blood that was peach in colour and about 1cm long. This period has so far, been 12 days long (normal length of 1 week) and been extremely heavy with lots of large blood clots. During this period, my coil came out. I want to know if I could have been pregnant and have miscarried and if I could get another coil fitted? Please answer this, many thanks, Louise