I think I have the answer to your condition. I have suffered from your symptoms. The first steps: Don’t stretch or exercise. You should be evaluated by a physician who is a pelvic floor specialist. They exist in several medical fields - neurology, orthopedics, urology. A good starting place is to look for a Sports Medicine physician. I would speculate that you have injured the pudendal nerve, which innervates the peri-anal region, perineum, and genitals. You can have pain in any or even all of those regions. Exercising, especially cycling, or even sitting will worsen the pain- sometimes not immediately.. Bending at the hip will worsen it as well. Conversely, lying supine or sitting on the toilet does not produce more pain. Many things can cause your symptoms, but my medical background says it’s likely to be Pudendal Neuralgia, PNE, CPPS (they can be related). A specialist will not just speculate, but will investigate using a diagnostic protocol for PN/cyclist syndrome.

The bad news: cycling is terrible for PN. So is bending.
The good news: nerves heal. Furthermore, any pain secondary to spasm in the pelvic floor muscles can be treated by a PT. The PT should also be a PN specialist. Some even do a new procedure called dry needling. Sounds scary, but perhaps it’s better than “internal manual work.”