I have a weird lip shape. How can I correct it and through what procedure?

My lips look kind of scrunched up when I relax my facial muscles. It looks okay when I am smiling but I can't always keep on smiling. It is narrow from corner to corner and asymmetrical compared to the rest of my face. Also I have noticed that the corners of my mouth are dropping and I am only 19. I would like to reduce the size of my lips if possible or at least make it look even. What kind of procedure do you recommend and where can I get them done? BTW I live in Los Angeles, CA.