Sounds in relation to the IUD it may not be the right thing for you. I had trouble with mine and had to get it out, might be best to get it out and go on another form of BC maybe the shots or patch or pills will work for you. Or this could just be a really bad period and you may have to get through it. You could schedule an appt with your gyno have them look but I have heard stories like this with the IUD personally it wasnt for me due to this very reason the over long horrible periods- everyone does different with the IUD. I'll never do it again lesson learned I now take the pill! Of course there are disease like endometriosis and other such issue a laproscopy or ultrasound and pelvic exam can find. But just could be that IUD!