Well, generally speaking, when dilated pupils occur, the black part of the eye will be bigger than normal. In other words, we can say that dilated pupils look like a big black circle. So just check it with your eyes. And in that way, your eyes may be painful in some degree. And also, if the cause is high blood pressure, it will just make your eyes feel stressed. By the way, some factors, such as high blood pressure and anxiety can cause pupils to be dilated. Besides, drug use, illness, and trauma are other causes. So just be careful about it.