Mirena and me question

Well I got mirena inserted in me on 8/14 and have a period for a few weeks, I had maybe a couple of weeks of being spot free and now I have been constantly flowing lightly for 43 days now. Not to mention, I was worried I couldnt check and feel my iud. They had checked my iud to see if it moved and it turned out nothing has moved, just the strings were cut extremely short. Anyone else have spotting this long? My cycle used to be every 28 days and 6 to 7 days long , but my main reasoning for getting this iud was because my cramps felt unbearable.