Thanks for writing in.
I would agree that allergies would not cause such symptoms.
A one sided blockage of the nose with watering of eyes is suggestive of a polyp or some mass in the upper-middle part of the nose which is not only causing the block pressing on the opening of the nasolacrimal duct
to cause watering of the eyes. The nature of this mass could be anything from a simple benign polyp to something more serious. I would suggest that you see an ENT specialist
and get yourself evaluated. Once we know the cause, we can start appropriate treatment.
Hope this helps.