Had excruciating pelvic pain so bad that it caused vomiting. worst pain i've ever felt. no cysts, bladder problems, etc. not pregnant. other causes?

See answer: Most common causes of acute, severe and potentially self-limiting pelvic pain in a young female would be kidney/ureteral stone, ovarian cyst rupture, ovulation pain (mittelschmerz), constipation-related bowel spasm. Endometriosis, pid, appendicitis less likely possibilities of acute, excruciating pain and usually have other associated symptoms. If symptoms persist or recur, md evaluation required.