Does she have to pitch?

[JEL]

ASA rules, (and any other which apply), girls fast pitch. Had a situation where at half inning, as defense was taking field, F5 takes mound and throws 3 pitches, then walks over to 3rd base, and original pitcher re-takes mound. This was done probably because offense had all girls out on field, (on deck) timing warm-ups. Offense posed this question, If F3 throws warm-up, does she have to throw at least one pitch to a batter? Questions are, 1. Was defense action illegal? I cant find a rule which applies. 2. Was offense action illegal? I found ruling which does not allow multiple on deck batters during half inning, is this enforced? I have never seen it but have seen the warm-ups by all batters. 3. I allowed play as stated above, did I blow it? I know both coaches were playing the mind game with each other, it did not seem to be detremental to the game, but what is proper action here?