You’re not going get far with Warrior and DK in 2v2 bracket. In 3v3 yes but you need any healing. The only 2x dps comp that really works is rogue + mage. I advice you to find a healer because you wouldn’t really develop as Warrior + DK vs Rogue + DH because it’s all about burst and Rogue will always have opener against you while he saps other guy.
The biggest problem with WoW PvP is that there is no instruction of mechanics or how to do things. Some mechanics like dimnishing returns or interupts are not even shown by default Blizzard UI and you have to download some. The fact that they didn’t add damage meters, DR’s on Arena frames or even Omnibar thing for all these years are just stupid.