I dont know exactly how much mastery i have but my shields are around 26.2k absorb. Im just wondering if my shield dissappearing so quick is ok? Like in twilight dungeons there are mobs that hit rather hard.

When i put my shield up its gone in 2 seconds...

What do i do ? Penance heal is mediocre to incoming damage. I have heard using heal is mana ineffecient as disc so if i use gheal im just burning through my mana. Do i just spam flashheal to get rid of that debuff to shield again ?