yeah i do moisturize, my skin is kinda oily, the problem is i frown when i focus, i am trying not to now,so i am looking for something to get rid of the lines i have now and prevent new ones from forming.
Have you ever tried mary kay targeted action line reducer? It's ok if you have oily skin (so do I). It's important to moisturize (with always oil free moisturizer) because women actually start to lose collogen in our skin at 15, if you can believe that. I have some frown lines too and I use the line reducer on my forehead and under my eyes...it works great.
May be your squinting a lot cause you need sun glasses! At 25 i would start looking into anti aging products. like a good spf cream, 50 if you can either a chemical or mineral cream, i like mineral creams as the other ones inrrate my skin!
You could also look into making your own vit c serum and once your skin gets used to this, may be even look into using a retinol cream, such as green cream, neostrata etc, or peels what ever works best really for your skin type!
Also using carrier oils, antioxidents and skin care supplements such as collegan tablets should all help you!