Are you sure you are seeing wrinkles...maybe you are. Have you been getting enough sleep lately. I would try that first. Relax and get a few more hours of sleep.
I agree with pp get more rest and drink more water, also start using a moisturizer with sunblock in it. see how that works and if you still see the wrinkles(which if they are wrinkles probably just mean you smile a lot) go hit up your local Sephora and see what they recommend.
Re: Wrinkles at 25?!