Lower abdominal pain, heavy periods, lower back pain and fatigue before periods. CAT showed cyst of ovary. Due to cyst?

Hi, I just went to the Er with a searing pain in the right side of my lower abdomen. Cat scan revealed a cyst on my right ovary , possibly from ovulating... I don t understand how ovulation could be that painful, I was literally doubled over and had to leave work. Also I have a paragard iud , and I have horrible periods lasting 10-11 days which are extemely heavy and painful, and have sometimes large clots.. They also start and end with a lot of gross brown blood, and have horrible odor all month, but especially during my period. Also have very bad lower back pain and fatigue for at least a week before and during menstration. Could I be having cyst problems all along and not have known about it? Or any other suggestion? I will be seeing my obgyn ASAP, but I am worried what could be going on. I am in a lot of pain, the Er dr said it might just go away in a few days, but so far it has not dulled. Thanks for your insight.