Starting out in Heroics you're gear was fine... IF you had CC. Honestly, it won't be until later epics (Kara/Bages/etc) that you can really tank more than one mob.
Sounds like your group just did not have the correct set up if you could not CC 1 of 2 mobs. Or were they un-CC'able? I can't remember the 1st pull in there, but I'm pretty sure they're sap'able or something.
Again, it'll get easier running Heroics with the gear. If you're not in a Kara raiding guild, get in one... asap. You're gear is more than fine to Currator, after that it's a bit iffy.
The one suggestion on gear is to get the Devilshark Cape from SV. It'll last until some SSC or something drop.
Your gear is fine, bring +stam food (spicy crawdad if you can afford), bring scroll of protection IV or V either. I suggest also getting Elixir of Superior Defense or along that line. 450 - 550 Armor don't sound like much, but it'll help.
Almost all epic'd out, and a buddy wanted to get a drop off Pandamonius (spelling?) and I'll tell you what... with no Shadow Protection at all... that's one hell of a tough fight. He owned us a few times, then I said ***** it and used everything I had... 1/2 hour, trinkets, HP stones, etc. So it's never a 'cake walk' but your party should have understood that you're learning.