Excruciating Pain In Rectum, No Normal Bowels, Had A Cystocele/ Rectocele Repair. Is This Healing Process ?

During a cystocele/ rectocele repair last May the urologist inadvertantly pierced the support bar through my rectum . I woke up in excrutiating pain, asked what was done there and was assured that was normal. Could not / can not have normal bowel movements still. I was admitted into the hospital twice after that surgery, a CT was done which showed an enlarged rectum, but still no one did a colonoscopy . I kept telling everyone that it felt like there was something blocking my ability to have a bowel movement. I was sent two months later to a proctologist who digitally and with some type of flashlight check me rectally and said that the first 15 cm were healthy and clear tissue, so it was probably just the healing process. Now, this January I finally get into a gastroenterologist who performs a colonoscopy and finds that indeed, I have a support armbar of the sling pierced directly through my rectum at 4.5-5 . My question is how could the proctologist of missed this?