Hello Viòlenza,
From what I see, you've a way to go in developing your character to attain optimal results. I notice that you are levelling Jewelcrafting, which is good. I suggest also that you drop Mining, as the profession gives you no benefit to your DPS, and instead level Inscription. This will give you access to an excellent shoulder enchantment, which you sorely need as you do not have any reputation with Therazane currently. Also, you need to put Power Torrent on your weapon, and I would exchange the orange gem in your Seal of the Grand Architect for a red gem as well as swapping the purple gem in your belt for another red. The hit the purple gem gives you is entirely wasted, so breaking the socket bonus has the effect of netting you 10 Intellect. Finally, the trinkets that you have are not very strong, especially if you plan on using Affliction. I recommend that to start, you get a Darkmoon Card : Volcano, which is easily available for reasonable prices these days, and a Rune of Zeth, which can be bought from the Avengers of Hyjal reputation vendor outside of the Firelands instance.
I think that if you make these changes and learn Affliction, you will see a meaningful increase in your DPS, as you do not have the haste rating currently to make Destruction worthwhile (2589 rating for a non-Goblin is all but compulsory at this gear level; 2681 is preferred).
For specfic tips on Affliction gameplay, please refer to the post that I made to these forums for Keesun :
viewtopic.php?f=27&t=15017Best,
Shinafae