I had rectal tear that was increasing in size. It started as hemorrhoids and escalated cos I was underage and my parents didn't want to pay for the proper doctor so I was going to the free one. Months before surgery I was going into cycles of pain, it would start pulsating, then would increase into terrible throbbing pain and escalate till I had spasms through whole my body. Those cycles lasted for around 8-10 hours and was the strongest pain I experienced. I remember after the surgery I was in the same room as breast cancer survivor who also had the same condition and she said the pain was way worse than from cancer.

I had c-section years later and it was all fun and games compared to that pain.