Well, generally speaking, it can be very normal for you to have this situation after you have taken exercises. We can say that it is because you are tired. As we know that when you have been doing some exercise, it will make your eyes feel stressed in a long time. We can say it as eye strain. Then after you finished, and see other things, it will be hard for your eyes to be accustomed to the situation around. At this moment, they can not focus on easily. So you should be careful about it. And you can just try some eye exercises to relieve your symptoms. Also, you can have some eye drops so that it can relieve the symptom.