Dragon Age II: Can you have more then one specialization class?(Also, questions about leveling up)?

I'm a level 8 rogue, and when it comes to combat, I really do rely on swordplay..So, I want to be a duelist. But how close am I to the end of the game? I ask this because I'd like to master both classes, well..Maybe not BOTH, but the duelist, I would love. I want to master in duel weapons..And I want to be faster in combat, not fast as in..I want to dodge every hit. I'm talking about dueling.



So..What can I do?



Also, I feel as if my guy isn't leveling as fast as he should be...I'm just now beginning the Deep Roads expedition where I visited the dwarf in the Qunari Compound. I often send my rogue against the alpha enemies..I spot the guy with the biggest health bar, and so I send my rogue after him.



When I finished Dragon Age Origins, I was a level 17 Warrior..I know that's a very different class then the rogue, but..I specialize more as a Rogue..Especially with the improved gameplay mechanics in Dragon Age II. I feel very comfortable as a rogue.Dragon Age II: Can you have more then one specialization class?(Also, questions about leveling up)?
Yes you can dual class. Leveling isn't affected by what YOU kill but what is killed and how much is killed.