I couldn't help with the healing time but it shouldn't hinder her arousal through stimulation of her clitoris as long as it goes through the hood and the hood alone - I've heard of instances where the piercing has done nothing to increase the pleasure but never have I heard of it making it less pleasurable.
According to
The Clitoris.com the vertical piercing takes 4-6 weeks to heal while the horizontal piercing takes 6-8 weeks to heal.
Enjoy.