When a stop click is revealed due to taking damage, how does that affect the damage taken?

Example:
Lydea Mallor is at click #4 (she has 6 clicks of life with a stop click on #6).
Opponent's Bullseye hits Lydea for 3 damage.
Stop click is triggered after turning the dial twice.

Will my Indigo character's Compassion be in effect?

I would say no. Lydea was DEALT three damage but the stop click prevented her from TAKING three damage. Compassion would NOT activate.

Taking damage is the actual clicking of the dial. If you did not click the dial three times, then you did not take three damage.