I just had my Paraguart IUD removed in December.
My period in December was 2 weeks late (probably from the trauma of having it removed, but has been my normal 31 day cycle with a very heavy period for January.
You are a bit ahead of me, but my understanding is that your period may get a bit lighter, but not by much, as a lot of women experience slightly heavier periods after getting the IUD.
I have also found from my research that not everyone shows a positive pregnancy test early on so if you think you are pregnant (which is a possibility since you have a very light period) you may want to go to the doctor to have the blood test.
Good luck! Let me know how it goes!