Amigo, consider that the key mapping is not fix, Textpad can for example be configured to use Microsoft compatible key mappings, then it is F3/Shift F3 for "Find Next"/"Find Previous".
And key mappings can be adapted to the user's wishes.
Thus irinetti could re-map the "Find Next" and "Find Previous" so that Ctrl-F or F3 (or whatever is configured) does "Find Previous" and Shift-F3 or Ctlr-Shift-F does "Find Next".
I doubt there's any key assignment anywhere that doesn't conflict with one somewhere else.
<Ctrl+C> means copy in most GUI applications but cancel on the command line. That's about as basic as it gets. One's fingers become accustomed to it; they work modally.