Irregular bleeding

I have an IUD and after I had it for a year i started to bleed nonstop for three months straight. I tried taking a month of birth control pills to steady out my cycle but as soon as I got off of them it went right back to how it was. I had that one removed and got a new one put in around September and it seemed to work fine, but my period which is usually a day or two is now at seven and counting. I don’t know if i’m worrying for no reason, or if it really isn’t working. The entire reason I got it put in was to regulate my period better. Anyone have any ideas as to what’s going on? I might also add that I did have some trauma last may which is when the intense bleeding initially started that included sexual assault. Thanks!