I am so sorry about your experience. It sounds like mine although I never felt well before or after the operation.
It was shocking I have regular colonoscopies the last one looked good then 7 months later was having stomach issues and doc would do test for cdiff, hpylori and could not find anything and Dr said I was fine, But I wasn't fine. Pain got worsen had Hemmroids and finally found a good surgeon.
Had another test this came up as colorectal cancer and said stage 2 cancer mass. Dr said best to. Remove anus, rectum and sigmoid colon and no need for chem or radiation. After 6 months had to
June 29, 2018 Colonoscopy
found 3cm leision was biopsied came back as adenocarcinoma
Operated on August 8, 2018 Had APR removed Anus, Rectum and Sigmoid Colon
Have Barbie Butt and permanent Colostomy
March 5, 2019. Cat scan found 2 non specific lung nodules
Surgeon going to watch and repeat Cat Scan in 6 Months Sept. 10, 2019
April 29, 2019 HyperDense Liesion 1.8 x 1.8 cm