Hitched medics (TMI) re copper coil

Had a copper coil fitted a month ago and got my period. It was fitted at the end of my last period and I had about 4-5 days of light spotting then fine then about 4-5 days spotting at the end of the cycle before my period started. Not normal for me but to be expected as the coil settles as I understand it. Now am bleeding heavily which is normal, with clots (also normal but usually they are small - about 1cm max) but these are huge (about 5cm diameter). How big should these clots be before I get concerned and is it just a matter of waiting a few cycles for things to settle down?