I AM A LITTLE CONFUSED, BUT IT SOUNDS LIKE YOU HAVE LEFT-SIDED ABDOMINAL PAIN. FIRST, STOOLS WHICH ARE BLACK CAN BE FROM SEVERAL THINGS - EVEN TOO MUCH VITAMIN C. BUT BLACK STOOLS MAY BE A SIGN OF PEPTIC ULCER DISEASE WITH BLEEDING IN THE STOMACH. THE ACID IN THE STOMACH MIXED WITH BLOOD FORM A BLACK STOOL. I DO NO KNOW WHAT TESTS YOU HAVE HAD. I WOULD EXPECT, BASED ON YOUR SYMPTOMS HERE, A CT SCAN OF YOUR ABDOMEN AND PELVIS AT A MINIMUM. YOU MAY NEED EGD, COLONOSCOPY, A TEST FOR H. PYLORI, AND THEN DEPENDING ON WHAT IS FOUND OTHER TESTING. A DR SHOULD CHECK YOUR STOOL FOR BLOOD, WHICH IS A VERY SIMPLE TEST. BUT IF YOU HAVE SEVERE ABDOMINAL PAIN, DO NOT IGNORE IT, IT IS STILL WORTH A TRIP TO THE EMERGENCY ROOM. I COULD LIST DIAGNOSES CAUSING SEVERE ABD PAIN, BUT IT WOULD BE TOO LONG.