If you didn't wear contact lenses while dust came into your eyes, you'll be okay, I think. Our eyes are weak and we need take a good care of them, or the beautiful world will abandon us. Dust rarely does harmful to eyes if your eyes have no any problems before. However, it is really uncomforable when dust entered eyes. Because no one will feel great for foreign matters. On the other hand, if your eyes already got injury or surgical operation, then you must have a deep infection when dust entered your eyes. If so, visit your doctor as soon as possible and make a all-side examination to ensure that your eyes are okay.