To start off: You are not a loser. I can practically hear you going, "Yeah, but you don't know how I feel." So I'm going to switch to the second part: you are not a failure. How do I know that? Here's how I know that: you are here and you haven't given up.
Life is messy. Even when we try our absolute hardest and plow ahead toward our goals, sometimes things don't work out. We fall down. We have struggles that seem bigger than we are. NONE of this means that you are a failure. Your struggles don't mean you've failed; they mean you're ALIVE. As long as you are still breathing you haven't failed, because you're still fighting.
"Are not two sparrows sold for a penny? Yet not one of them will fall to ground outside your Father's care. And even the very hairs of your head are all numbered. So don't be afraid; you are worth more than many sparrows." — Matthew 10:29-31
Your value is inherent. God knew before you were born that when you were this age you were going to go through some times that were difficult. That does not reflect on how much you are worth (which also means you are not a loser). Realizing your true value to God is also important in combating the lie that you have done nothing productive with your life. Also, I'm going to say that adult thing they always say: you seriously have your whole life ahead of you. You have no idea what you can and will accomplish!
When we're in times that nothing seems to be going our way, it's easy to think nothing has ever gone our way and we haven't accomplished anything. If it seems you've done nothing with your life, you may not comprehend what kind of impact you may have had on others—your little sibling, your neighbor, your hurting friend, that stranger you smiled at... And that is worth more than any good grades, pats on the back, or trophy-winning achievements.
Sometimes our goals and His don't line up. Goals are awesome, I am a huge fan of goals. But if God opens up different doors than what you have written down as your goals, don't view that as a failure. View it as God has a different plan. Jeremiah 29:11 says, "'For I know the plans I have for you,' declares the LORD, 'plans for welfare and not for evil, to give you a future and a hope.'"
If you aren't praying already, pray every day for God to help you through the next 24 hours and ask Him to help you see how His glory shines in your life. Maybe it's in that amazing sunrise or the clouds in the afternoon. Maybe it's in you giving up your seat on the bus for someone else. Maybe it's in how that little child smiled at you. Keep your eyes open, and you will see Him right there in your life.
You have value and the God of the universe CHOSE you, adopted you into His family. HE CHOSE YOU. I realize that sometimes it's hard to truly believe that, but it's true nonetheless. How can you be a loser when God loves you? How can you be a loser when God chose you? He knows everything about you so it's not like He doesn't really know what you're like. He's seen every dark thought and action you have ever had, and despite all this...HE. CHOSE. YOU.
You are not a loser. You are not a failure. How do we know this? Because you're here, and you haven't given up. Your value is inherent (Matthew 10:29-31). God knew before you were born that when you were this age you were going to go through some times that were difficult. But your struggle doesn't mean you've failed. God has chosen YOU, and you are a precious child to Him—no matter what happened in your past, present, or future.
Heidi Joelle spends her days staring at paperwork and making sure it is where it is supposed to be, how it is supposed to be, when it is supposed to be. And then she comes home and makes sure the porky little dog isn't eating a trashcan. Between these two events she tries to learn and see as much of the world around her as possible.