Achieving Black Belt status requires more than focusing on yourself. You must develop your technique and support others in developing their technique. By helping others you continue to develop your technique because you become familiar with others' movements, needs, and gaining a better understanding of the receiving side.
By utilizing other resources outside the dojo you can accelerate your training. Consider joining an outside gym and build your endurance as much as possible. As you build your endurance and strength you will be able to jump higher, hit harder, and out maneuver your opponent.