IUD Expulsion?

I think my IUD might be trying to expel itself. I had the Mirena IUD inserted this past November, and my periods have not yet regulated themselves. After checking for my iud strings today, I found the strings hang out of my vagina. Currently it feels like the device is in my vagina, similar to the feeling of not putting a tampon in far enough. My vagina is tender and felt oddly swollen? I’ve been bleeding since March 20th except for one day, with cramps and all. I have previously been diagnosed with endometriosis and have undergone treatment. I’m worried my IUD is in the process of expulsion, or may be displaced. I’d appreciate any advice from people with similar experiences with iuds.