Hi. I guess you must be having a very bad cough due to the pneumonia
. Severe coughing
can sometimes be associated with such symptoms like transient blurring of vision and light headedness. But persistent/ sustained blurring of vision cannot be explained if present. If you have persistent blurring of vision in one or both eyes, you may consult an ophthalmologist for a thorough evaluation. Hope I have answered your question. Thank you.