Lots of post nasal drip for 2 months/mild facial swelling. could be a sinus infection. any solutions?

Yes: Get rid of anything that have caused that. Start an over the counter decongestant. If symptoms don't improve see an allergist.

A few things..: You can try a neti pot- rinsing out your sinuses can be very helpful. You may also try a short course of oral decongestants or an antihistamine with a decongestant in it (like Claritin-D). You could also benefit from a prescription nasal steroid- you may have chronic allergies causing your symptoms. Humidified air may help with the facial/sinus swelling.