help?

So I have been on xarelto for a year and I had the IUD Paraguard put it 6 months ago. My periods are insanely bad bleeding and clots. Well I stopped taking my blood thinners for a month and my period is working on two weeks late. I took 2 tests on different days for pregnancy and they both came back negative. Has this happened to anyone else? Paraguard is known for making periods worse not better.