Severe pain not sure what it is

[sras1234]

I have been having sharp pain in my lower left abdomen, left hip and more recently (last 6 months) i have been having the hip pain shooting down the back of my left leg, sometimes to my ankle.  I know that can be a symptom of sciatica, but it is accompanied with serious abdominal bloat throughout the day, usually i wake up looking normal and go to be looking like im in my second trimester.  I went to my obgyn and they did ultrasound, found nothing they said.  still in so much pain, not sure where to go at this point.  I had gone to my primary care doctor after I had my son 2.5 years ago with this issue and they said everything was fine.  Obviously, its not fine to me, I am in so much pain i can barely sit, due to back and hip pain.  I freak out about it being cancer or something. I had Puerperal endometritis right after giving birth, but cant find anywhere that it would cause long term symptoms.  I am going crazy about what to do and am really giving up on doctors since everytime i go, they say nothing is wrong and to just take motrin.  Which I do and it doesnt help.  Any advice would be greatly appreciated