Such is life! Sometimes you win and other times you lose. But because you lose doesn't make you a loser, except you see yourself to be so. You should learn that it doesn't always go as we planned in life. Sometimes disappointment becomes inevitable, especially in your case you've practiced tenaciously, and yet, things didn't still work out as intended.
There is this general adage that "he who fights and runner away live to fight another day." Because you achieving your goal as at now didn't come to fruition doesn't mean if you try again someday, you would not nail it. In addition, because you failed in realizing you goal for now is not a reason for you to despair. Instead of been discouraged and be wallowing in self-pity, get yourself motivated and keep your hopes up, believing that whatever that made this your goal to fail is a blessing in disguise, and that bigger opportunities lie ahead on the horizon, if only you still have undying determination to give it a try once again.