For a month now, I've been having severe pelvic pain, lower back pain, constipation, and nausea. Went to Dr. Did urinalysis...all clear. Sent me for ultra sound. Found shadow on left side. Now scheduled for CT scan wed. I haven't had my period, and I'm in no way possibly pregnant. I'm 43, and a lesbian. So pregnancy out of question. Should I be worried about endometreosis, or cancer? I'm very scared, and hope to get answer wed. after CT scan.please give me ideas on what it could be. I'm a smoker.no kids. Thank you, Kari.