Well, first off, target dummies are more for practicing your rotation than getting an accurate idea of what your raid dps is going to be like. You're missing buffs you wouldn't normally have, and that is going to affect your dps some. 12k though is pretty bad at your gear level though. =/ I'm not an expert at fire mage, but try to describe what it is you do for a rotation and I"ll see if I can give you some tips. Also keep in mind though, Fire really shines in multi-target situations because of their awesome AoE. They still do pretty good single target dps, but not near as good as their AoE.
Guild Wars 2, Crystal Desert server:
Inga Freyasdottir, lvl 40 Norn Mesmer
Deathbringer Kaami, lvl 16 Asura Necromancer
Popina, lvl 15 Asura Elementalist
Althaia Willowbark, lvl 7 Sylvari Engineer
Maeve Amnell, lvl 4 Human Guardian The MMO-Zam's FB group.
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