You're 19, and you're worried about it? Jeez. I'm 27, and every day I feel like it's just one more day I've accomplished nothing, and am closer to death. Beautiful outlook to have, yeah? The last thing you should be concerned about losing, however, is your beauty. Looks fade, but who you are inside remains. As such, I figure it's most important for us to focus upon edifying ourselves from the inside out, because honestly, when we're all dead and buried, are people going to remember how we looked primarily, or how we affected them in every other way?
That said, anti-wrinkle cream is good. But not at 19! Give yourself a good 6 years before you really start panicking.
SD