I am sorry you are dealing with this. This is going to sound strange, but I once baby-sat for a little boy that had a strange odor coming from his nose. His parents finally took him to the dr. The dr. I think used a lighted scope and found a rotten bean way back in his nasal cavity! Sorry, that's pretty nasty! You know how kids are, he was probably messing around and whoops! there it went!
Now I know you are an adult and I'm sure you don't stick things in your nose, but maybe something inadvertently got lodged in there. I think you should see an Ear, Nose, and Throat Specialist (ENT) and hopefully they should be able to see with special instruments if there's anything amiss in your nasal cavity.
Good luck and I hope you can get some answers soon. Keep us posted!