Abdominal pain and bleeding?!

Abdominal pain and bleeding?

For the past three months I have had LLQ pain which has increased in severity -- the pain now radiates upward in a line to my belly button. The pain feels like a heaviness or weight in my abdomen. From the middle of May until the middle of June, I passed tissue-like clots streaked with blood. I have bad lower back pain, am very fatigued. The pain sometimes "flares" up and becomes even worse.
Last night I went to the emergency room, because of tingling/tenderness on my right side from scalp down to my arm. I blacked out from the pain and was unconcsious for a couple of minutes.
The problem?
I have had pelvic exams, blood tests, pregnancy tests, pelvic and abdominal ultrsasounds and they have all found nothing. The ER doped me up on Demoral and sent me home, saying that nothing was wrong.
I am seeing an internal specialist tomorrow and would appreciate any personal experiences, thoughts or questions which could lead me and my doctor to discovering what is wrong.

2 weeks ago
Thank you for all of the answers so far. As I said in the question, my pelvic ultrasound came back normal, so it cannot be cysts or tumors. I saw a gyneocologist today who said that it cannot be endo (although I have my doubts) and that I should not come back to her or any other gyneocologist for pelvic pain.
I am trying to brainstorm for the appointment with the internal specialist tomorrow, so I am looking for possible gastrointestinal causes. Thanks again.

This sounds like a Gynecology issue. You could possibly have Endometriosis. I have recently been diagnosed with it and I have a lot of the symptoms that you have. I have had 3 children and never had a problem with it before but about a year ago I started having SEVERE abdominal/back pain, HEAVY, irregular menstrual cycles, fatigue. I had exploratory laproscopic surgery in January and they confirmed the diagnosis. (That's really the only true test to confirm it.) You should really see your GYN.