I have had pelvic pain on and off for years. I did have an endometrioma years ago, which caused some pain, but otherwise my pain came from adhesions from the endometrioma surgery and from muscle pain. There are several muscles in your lower back and abdomen that cause pelvic pain. Most of my pelvic pain actually originates from the iliopsoas muscle. Try getting a massage and see if that helps. If it persists, and it's not muscular in origin, you may want to request an ultrasound. But, seriously, pelvic pain is so common - especially in women of child-bearing age. Don't worry!