Iud & bump on cervix

I was checking my IUD(skyla) strings last week  and found a bump on my cervix. I made a doctors appointment for Thursday. I have had my iud for over a year but through out the last week I was cramping very painfully and expected I had another ovarian cyst. So following the pain I decided to check my iud strings and found the bump. But I was wondering if anyone has had an experience like this. It's a hard bump and a little bigger than the size of a pea near the opening of my cervix and it hasn't changed in a week. Any advice or experiences would be helpful!