First time healer, Playing Shaman, few questions..

I'm leveling with it, it's going fantastic overall (lvl 50 in 8 hours of played)--i've never actually died, which is just astonishing.

But i've had 4 people in it die--one got nuked, no idea what he did, just 100-0 in an instant.

And all rest of the 3 died in the same place, the last boss in the Underrot--and all of them a split second before the boss dies. What on earth is getting them? I cant possibly heal through that, what ever in the heck it is--but since \*I\* am not dying there, i have to assume i'm missing or running from the thing they're not. One time it was even our tank that died--he went down and 2 seconds later the DPS finished the boss.. it's always that close to the end. What's going on in that one that's getting people?

Also--sometimes i get swamped, DPS starts to pull everything the tank intentionally did not--almost like trolling us all. No one's died yet, and it's taken *insane* effort sometimes to prevent it. Is this just trolling--it seems *way too* intentional for it to be anything but intentional. Is this ... normal, and expected once i get to mythics? Because i'mma need to up my bloodpressure meds for that if so.

And last thing--while leveling through dungeons (i've never done any dungeons since BFA was the actual release, and then only for quests), i'm almost always first or second on the dps, *as the healer*, and i ... hate it. I feel like we just *wont* progress through these things if i stick to heals... wtf are the dps doing? Nothing? Bots? Or is this a scaling issue? Is a healer supposed to be anywhere even *close* to the dps--or down below the tank? I've got no idea, because, like i said, i dont even run dragonflight dungeons otherwise on my 70's.

Also, any advice moving forward, especially as i start to get close to 60 soon, and head for dragonflight healing?