Why in the world are you even considering it? From your picture you have beautiful full lips that dont need to be touched. Dont make the mistake and have anything done. You are far too young and you look great. Trust me!
I would wait until you are fully matured to think about anything like this being that you are still growing.
At age 13 your face is still changing and I think it is a bit too early to get fillers. Why not wait to see how your face grows as it will be changing a lot in the next few years. Best, Dr. Green
Your lips may continue to fill naturally as your age. The truth of the matter is many individuals under the age of 18 come to facial plastic surgery offices very adamant about having surgery, but are too young. We surgeons would be doing you a disservice by changing your facial features before your facial features have yet to form fully. Who knows - you may even turn 18 and find your lips have filled out more than you imagined now at age 13 and then, desire lip reduction.
In short, remain patient and keep in mind that your mental health is just as/even more important than your physical beauty, although your mental health is often tied to your impression of yourself. Take comfort in knowing there is always the option of facial plastic surgery further down the road. Why don't you spend the next few years learning as much as you can about facial plastic surgery so you are well prepared to meet the surgeon when the time comes and if you still have the interest.
Digital photography rarely tells the whole story, but I was expecting to see smaller lips when I viewed your photo. If you are having severe dissatisfaction with the appearance of your lips, you should inform your parents for guidance and direction. They may be the best resource to help you decide what might be best moving forward.