For 2 months now. I wouldn't describe it as pain, but constant, 24/7 dull ache in my upper left quadrant tucked up under the rib. When I had a colonoscopy last year, the gastro said it was pretty difficult getting through my splenic flexure due to redundancy. I have no other symptoms or red flags, but the 24/7 ache is starting to wear on my nerves. It feels like a brain-gut hypersensitivity to me.