MOBS wont drop Quest Items to my character

I was leveling a Orc Warrior in MoP's Frostwolf realm, when suddendly, Quest Items stopped appearing, i mean, in the first minutes i thought their drop rate was extremely low and i kept farming, after 30 minutes y realized it was a bug; ALL other quests items were not appearing aswell, even those with a high drop rate. I think my character Durotax got bugged, how do i fix this?

PD: I tried deleteing Cache and WTF folders, but it didn't work, i lost all my settings and now when i try to chance the resolution to a smaller size, the screen just gets tiny in the middle of my monitor with black background on the sides, can somebody share a Config file, please?