butt release tunnel valve 🙄

Kay, the sensation of “crapping razors” is often a sign of an anal fissure. If that’s what you’ve got it can be treated with cream/ointment containing nitroglycerin, nifedipine, or diltiazem. You can also try cleaning yourself with a spray bottle or bidet instead of toilet paper, and soaking in warm water (a sitz bath) might also help.

Kay, the "shrinkage" sounds like a stricture. This is when some part of your exit is narrowed, and can cause bowel movements to be thin (like a pencil) or very difficult to push out. Don't push because you might cause hemmoroids or more fissures (the feeling of razor blades!). If you can get an appointment with your surgeon or GI, they can stretch your stricture, if that is what you have. Use a bidet bottle, as Scott suggested, after every BM, and no wiping with dry toilet paper. A bidet bottle, and a sitz basin, can be bought at stores that sell home healthcare equipment, or on Amazon for approximately $15 each. Not too expensive, and it can soothe and help heal your bottom.