Fiery dragon sword

I just bought a fiery dragon sword. The reason is cuz im a W/E and im all fire and i just got this skill that deals extra damage on fiery swords so i used it and it was good but besides that the dragon sword only deals like 8-15 damage its so much worse than my other sword on damage it says it deals 15-21 like my other sword but it doesnt. Is it the animals or something?

They most likely have a resistance to Fire damage. What were you fighting? Have you had the weapon customized yet?

It could be the creatures your fighting are resistant to fire.
Do you meet the minimum requirements on the Dragon Sword?

I was fighting at druids overlook with the carrior devorours and the feverd devouros. its req are 8 swordsminship and i have 12. but i will customize it thats a good idea i forgot about that.

The enemy in the game comes with different armor ratings. Your hit +/- its armor rating = your hit

(once you customize your weapon to you add +20%, some weapons deal extra damage, and have different attribute that might also cause that creature more damage - Max dam is only one part of the damage calculation)

scorpion like things are pretty resistance to fire, as I play a pyro/dom ele. Go further a bit and check your damage on those animated bamboo like guys ... forgot the name, but i get 20%-30% dmg on those.

Reed Stalkers, Thorn Stalkers?

What's your strength at? It could be as well that youre not penetrating the armour that well and therefore reducing the overall dmg.....of course mixed in with any resistances the mobs have like Fire etc.
Also, is that 8-15dmg w/o using a skill...just simply hacking/slashing at them?