The problem isn't in my nose, it's in my brain! I guess when I was right there, rodding out the line, and the smell was overpowering, my brain shut off the olfactory nerves so I wouldn't puke or something. But instead of letting it go, it stored it in memory only to haunt me at a later undisclosed time and place.
Thankfully, I haven't had a relapse since last night. I'm keeping my fingers crossed.