Michael, its never about the age. Some people needs to think of it in their early 20's and some start in their 30's. What matters is,the type of skin and its texture. You may have a glowing bright skin or dull saggy skin in your early 20's. I suggest you to visit a Dermatologist, know your skin type and treat accordingly. 25 is the age when your skin starts regenerating once in a month unlike that in 15 days when you were young.
If you see fine lines near your laugh line and near your eyes, you should definitely go for a good anti aging cream and try to avoid Sun as much as you can without a sunscreen.