What Is The Treatment For Severe Pelvic Pain?

Hi, I'm a 24yr old female, 62kgs, 170cms. Been suffering from intense pelvic pain - sharp twisting feeling. It comes and goes throughout the day, and can wake me up in the middle of the night. It is really intense pain, and painkillers do not help. I had this problem 2-3 years ago, and went through many tests, ultrasounds, exploratory surgery to no avail and no concrete answer. It went away, so I stopped worrying. But now it's back, and worse than before. It gets a little better if I have a bowel movement, although the pain will persist for 15/20 minutes. Any suggestions?