Eyelid is swollen eye is watery an blurred vision and also sometimes pain in eye an sharp head ache pains on the same side. What could be the cause?

Get Eval. The answer depends upon how long you have had it, how much vision disturbance you have, whether it is strictly one-sided, your age, other health, and other criteria. However, some significant problems can be related. Get ophthalmological evaluation. Depending on what is seen the doctor can refine the possibilities. Consider Cluster HA, SUNCT syndrome, cavernous vein, glaucoma, other.