Tanking feels really uncomfortable at times

Level 25 warrior, I've tanked RFC, WC, and BFD. I noticed the problems started happening in bfd dungeon when others get their AOE and mobs start hitting harder.

Lot of my groups just don't listen to mark kill order so aggro isn't all over the place. Mages using Bllizzard and spamming arcane explosion causing 4 mobs to run at them and I can't do anything about it.

Then there's the mobs that run away and aggro more mobs. I've died a couple of times and the last time it happened, I got blamed for not killing the murloc running away and pulling more enemies when I already have 4 other mobs on me and trying to keep aggro. Aren't DPS supposed to be the ones to make sure the stragglers die?

Also hunter pets. They always seem to have growl on so I lose aggro constantly and the hunters never respond when telling them to turn it off. I hope it gets better, I just feel like being blamed for stuff out of my control is going to get old fast.