I'm going through the same thing and, yes, it does have a lot to do with being a teen. I'd just suggest finding a good moisturizer, foundation, and cleanser for the makeup ordeal (liquid foundation is a bit clogging, but it looks better during the daytime oh and use primer). I'd check out Sephora or La'occtaine (whatever they are called) for some moisturizer - I have no idea what your skin type is like. Acne isn't something I've solved yet, but with luck it'll go away with age (sucky acne). Go in to talk to a consultant for any problems with acne or go to a makeup booth to ask for what they have to offer.
No matter what, makeup isn't going to make you feel beautiful unless you already accept that makeup is an enhancing product, not a covering product. Clothes and general hygiene help: if your hair is greasy, try taking showers in the morning with a shampoo specially for greasy hair with a light conditioner, but looks aren't really the determining factor for confidence. Experiment with different products that are right for you.
If you are a average teen, like you say, it is because of internal issues that you feel the way you do. You are an average teen. Average teen = racked with self doubt
A lot of this has to do with how we compare ourselves against others. For example, I thought I was pretty good/normal looking when I went to my middle schools (big-busted, fairly clear skin, okay teeth, etc), but when I got to highschool my self esteem went into shock. All of a sudden I was small-busted, short, ugly, acne-ridden, with yellow, awful teeth...why? Sure the girls at my highschool are beautiful, but mostly because I always look at them like they are somehow better than me. My self esteem changed because I felt threatened and insignificant to these other girls (my looks didn't drastically change overnight). So, if you're anything like me, think in terms of "different", not "better".
Many-a-things in the world are what they are, and the only thing you can control is how you perceive it - that's how your esteem can change so quickly and to such a large extent. The problem with being inside our body is that we can't see how beautiful it is, just like how a person from America can't possibly realize how important and powerful each citizen's rights are. The grass is always greener on the other side, right? As you'll always hear from people: SMILE. Not only because it usually makes you prettier and makes others feel good, but if you try it enough your smiles will be genuine. It's a scientific fact. To be confident, act like it. Get some good-smelling soap or lotion to make you feel pampered. Talk to some new people. Work on some hobbies - find some new hobbies! Try something fun and exciting!
Whenever I get like that, as corny as it sounds, I like to think of the trees or the sky: one day it's overcast, one day it's cloudy, another it's blue from the horizon to the apex. The sun or moon is always in it though, correct? Just some times it shines brighter than other times. This is your talent, your beauty, your worth - it just is covered by clouds of sadness, anger, self doubt, and insecurity sometimes. It's still there, you just can't see it. Like my grandma always says: "Don't hide your light under a bushel." Whenever we can see the sun or the moon clearly it is always beautiful, though. Those clouds will dissipate soon, I hope. More often than not, the only one making us feel bad is ourselves and our self-criticism.
I hope this wasn't as ranty/preachy as it felt for me as I was writing it. To be short: you're beautiful, not because you look like a model, but because you are a fellow human being with a compassionate heart and unique traits and talents, which all outlast any form of beauty that is physical. I don't know how low your self-esteem is, but I hope this a least made you think something new.
Sorry if I wasted your time!
Best of luck! XD
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