Reminder.... one does not have to be taking an ACE drug to have excess bradykinin. It will just happen faster.

People who have problems metabolizing bradykinin away, will always have it....see that link I provided earlier about HAE.

Bradykinin exists in normal amounts in people with C-1 inhibitor actions. It is the body's reaction to physical and chemical trauma
stimuli that releases it. People with defective C-1 inhibitor have long reactions to bradykinin therefore. (this is acquired and/or genetic or both).

The FORCE of the water from a shower is more likely the culprit.
Temperature of the water also a factor. Some people on our PN forum react to Chlorine in pools with pain.
If you can slowly pour lukewarm water on yourself slowly and not get a reaction....I'd look at the force and temperature of the shower itself as a trigger.