In a particularly severe case, you could combine methods.
i recommend:
1. Fill toilet with large quantity of ice cubes, and wait 5 mins for water to become very cold. Do not over-fill as you must retain splashability.
2. Do your thing, while setting off mousetrap on fingers simultaneously. If mousetrap forgotten or unavailable, slamming the door of the dubs onto your thumb, or in case of unsuitable door, poking yourself in the eye, will work equally well as a distraction.
3. Dip one of these
into a pot of Greek yoghurt
(Other products such as Calippo can work well, but the Zoom caters for a wide range of sphincter apertures, and if the end breaks off, is less prone to falling back out)
4. Insert rectally. Lave as long as liked. If in hurry, break off and leave sharp end in situ*
* If time is tight then you should acquire some of these, or similar
If used, consider in particular strife inserting small bag of frozen peas in gusset