I'm not so certain that the issue is the definition of the term normal, so much as it is the value (positive or negative) or association (healthy vs. unhealthy) the term implies in a medical or social context.
One of the most common reasons for blurry vision while wearing contacts is that your eyes are dry. Some people have a medical condition that causes dry eyes, called dry eye syndrome, but others' eyes are irritated by the contacts themselves.
Next FAQ >. Contact lens discomfort is a symptom that something is wrong, and you should always take it seriously. Eye pain from contact lens wear is particularly worrisome, because it may mean you are developing a contact lens-related eye infection or other serious problem. If you develop sudden eye pain when wearing contact lenses or your contacts hurt, follow these steps: