This is because the eyes may try, without success, to correct the blur, and because there is a tendency to screw up the eyes to try to see better, producing discomfort in the muscles of the eyelid and face. Sometimes correction of astigmatism can cause change in the apparent size and shape of objects and may affect judgement of distance. A patient may feel taller or shorter, or walls may appear to slope and floors curve. In most cases, adjustment to these side effects takes only a week or so. Astigmatism correction may involve a compromise between optimal clarity and visual discomfort.
Some people notice blur themselves.
Only a proper eye examination will determine for certain if you have astigmatism. Astigmatism is not an eye disease and any changes are generally gradual and not necessarily for the worse. Most people have at least very slight astigmatism. Presbyopia is a common condition which makes vision difficult at a normal reading distance. It is not a disease.