Vision decrease at 22?

I've had 20/20 vision my whole life. When I was 22, I started to notice things becoming uncomfortable distance wise. I had a harder time reading from far away. Things were not as brilliant as they once were. I had not had my vision checked since I was 18 -19 years old, so I can't tell you when my vision started to decrease exactly, but I noticed it more at 22. I am now 24 and have been to the eye doctor three times since. My sight is only slightly stigmatized with a slight distance problem. My pressure test came back a little high but when I saw an actual eye doctor he measured with his own tests, it came back fine. Is it normal to loose vision slightly at the early 20 mark?