I had a similar thing in September and I think it was viral. I also had headache and diarrhea.
following to it I started having muscular weakness.
any ways it's probably something involving your sinuses a few months after I was found with mucous in the sphenoidal sinus don't know if it was a coincidence.
were you in a crowded place before it happened?
keep a log of the event and the symptoms.
So which is it, your nostril or ear?
Usually this fluid accompanies a cold. It can also be spinal fluid, but that would be very rare and usually associated with trauma. It is not terribly unusual with colds, although it may only happen to you once in 20 or 30 years.