Is this allergies? Or ... What?

(Other than just annoying).

About a month, month-and-a-half ago, I started developing an odd symptom that’s really driving me crazy. On occasion, with no provocation I’ve been able to determine, I’ll suddenly get a -very- intense itching / tickling sensation in one of my nostrils (not always the same one). It feels like it’s about halfway up the nose, and immediately my nose will start filling with mucous. I don’t know what’s causing it and it’s getting very annoying, so I turn to the dopers to see if anyone else has this symptom, if there’s anything that can be done about it, and if it’s a matter of allergies or something perhaps even more annoying.

I have nasal allergies, and that…that seems kind of strange.