J.K.
I got the paraguard when my son was about 7 months old, and had a similar experience. Lots of cramping and heavy bleeding for alomost a week. There were small clots, but not large. If you're concerned at all, I would definitely call the nurse.
My periods following the insertion were heavier and more uncomfortable the before, but the last 1-2 were better.
Hang in there! =)