I have been having attacks of proctalgia fugax for decades, usually about once per month in the middle of the night. They are terrifying, with pain so intense that I expect to faint.
Over the years I have tried tremendous numbers of remedies, and for myself at least, I have finally found a reliable protocol that has been consistently helping over the past couple years (by the way, I totally see how the TENS unit could do the job...this is one that I haven't tried but I expect it would work).
For me, it seems that proctalgia fugax is related to a little bit of gas that is trapped in the colon, perhaps in a tender spot. In the last couple years since I tried this remedy, the attack ends with the expulsion of gas.
What I do is, once the attack has begun, I lay belly down and pull my knees up to my underarms, and push my chest/belly down to the bed so there's a big stretch in the anus area. Then I bounce my buttocks up and down on the bed hard to create lots of jostling. I alternate by putting my knees together so that my thighs are bumping into my belly when I jostle. Another thing that helps is to squat on the floor, put my hands on the floor or a table to steady me and bounce my buttocks up and down so that they are hitting against the back of my feet.
Basically I am trying different movements to cause my bowels to move around inside. I have also done belly massage, and lie on my back and pull my knees up and hug them and roll around back and forth side to side. Then pull up one knee at a time and extend the other...sorta like what you would do with a baby with colic..."bicycling" in the air with your legs to move the gas around.
This basic body movement has been the most helpful in relieving an attack fairly quick or at least reducing the pain of an attack substantially.
Another thing I've done alongside this, and I'm not sure how much it helps but I have a hunch that it contributes to success, is the homeopathic remedy sepia 30C.
Furthermore, acupuncture is probably really helpful too, as I have been seeing an acupuncturist for the past year, and just today noticed that I have not had an attack in the last 6 months until today, and today's attack was solved within 2 minutes, which has NEVER been the case for me in the past.
My husband has struggled with this for a number of years now; & it seems that if he consistently takes a supplement of magnesium & potassium, he finds relief.