Rectum Pressure Frequent Urination

I was in an accident a year and a half ago, I now have pressure in my rectum, and find my self with bladder discomfort, I have had a colnoscopy, a cystoscopic, sonograms, ultra sounds every test has come back negative, so far everything has come back to my back injury, damaged nerves, I feel like im loosing my mind, I have never experienced anything like this before the accident I feel like im living in a nightmare, if anyone has any info please help, I know in men its called prostatitis, can your nerves really cause so much discomfort. Help