Well, of course, contact lenses can not really change the color of your eyes. Actually there are some types of contact lenses which are named as colored contacts. Generally speaking, colored contact lenses are used to change the color of your iris, either giving new hues to the original color by means of a barely colored lens or modifying it massively with intensely colored one. But when you take off the contact lenses, your eyes will look normal. On the other hand, color of the eyes can change with the different emotions. If you are embarrassed or excited, your eyes will turn to red ones.