Originally Posted by YeastFarmerBeemer
I don't think a wild yeast would make it smell really bad, slightly off at most. I am currently stepping up a wild yeast that I harvested from apples off our backyard tree and it smells like yeast (well actually it is starting to smell like yeasty cider since I used apple juice for the last 2 step ups).
Also the smell "burning your nose" could be co2.
You have all different kinds of wild yeasts. The ones found on fruit are usually pretty nice and clean from what I've read: someone here even cultivated the yeast from juniper berries.
It's the airborne, "living by the highway in a tiny appartment", kind of yeast that can mess a good brew. But that's just speculation since we don't even know if something other than yeast has been getting its funk on in OP's beer.