Low level dungeons are nothing to worry over. The Tank sets the pace (unless you have some really dick-ish Dps), and as long as you declare you are new at the start most people tend to be forgiving.

My suggestion would be to always play it safe your first time that you run a new dungeon. Having great AoE control and knowing how enmity works is great, but knowing the actual dungeon can be more important, especially at higher level content. The first time you go in a dungeon you won't know where everything is, and you won't know if there are monsters who have special attacks, AoE's, or status effects. Pulling big in Sastasha will probably be fine, but if you try the same thing in Quarn the first time you'll probably get killed by Final Sting and not know what happened. So, my general rule of thumb is to play it safe until you actually know the dungeon.

It's also a good idea to keep an eye on your healer. I almost always "examine" my healer to check out their gear, and I don't pull more than they can heal. If the "one or more party members has not completed this duty" sign comes up at the beginning, I ask who it is to check if it's the healer. I do this, because even if you know the dungeon inside and out it won't make a difference if your healer can't keep you alive.