IUD, too replace or to not replace

Hi guys!! I have a mirena iud inserted in my cervix and almost every time I have sex I bleed or get for example last day of your period brown discharge. I DO NOT like it, as it’s annoying but I love my iud because the chances of pregnancy are minimal in comparison to other BC. Recently I was assaulted and had my period but this time it was a horrible period with crying on the bathroom floor and diarrhea:( I went to check for stds and my dr noticed my IUD was falling out. Should I replace it or do you guys have any BC you recommend?

Also if you have an iud, do you bleed after sex?