First and foremost - don't worry so much. You are and will be perfectly fine. You are funny, positive and loved. You might not be where everyone else is - but it doesn't matter. You are where you're supposed to be.
Every choice you make will lead you somewhere great. The good and the bad decisions. All the shitty stuff will turn into something awesome. Just trust it.
All the people you meet will play a huge part in your life. Take care of the relationships that lifts you and let go of the ones that drags you down. Also, be the person that will help lift others. You will have amazing friends and your family is gold.
Again, don't worry so much. Trust life. Trust yourself. Don't let other people decide your life for you, but don't turn down help. People need people.
Listen to your mother. She's almost always right. Take care of your relationship. Just let it happen. She is the best, even though she chews loudly and talk to you in the morning - even if you tell her not to. Because, parents.
Be kind. Be brave. Be fearless.
Remember, wear clothes that you feel comfy in and that you actually like. Don't wear weird stuff just because the other girls wear 'em. Like the low waist jeans. Just. No. Don't worry - you'll find your style.
Be proud of your long legs and big feet. You're awesome.
Put down the cigarette. It sure looks cool now, but it wont look cool in 10+ years. Trust me, it sucks. It will haunt you forever.
Eat right and skip the energy drinks. Thank me later.
Skip the black eyeliner, or take time to learn to put it on properly. Seriously.
Take your time with a boy. Get to know him and make sure he treats you right. You're not in a hurry, and if he is - dump him.
You will travel, alot - but remember to enjoy it.
Love yourself. It will be the most important relationship you'll ever have. Be your own best friend and you'll never be alone.
Most importantly - you are enough.
..and boybands are still awesome.