That why you need to begin from the basics. Forget the sparring, forget the combos, put all that aside for now; you need to start from the very beginning. As in how to stand in a good stance. What that is will depend on whether you're doing kickboxing or Muay Thai, and later on, what your fighting style is like (punch based, kick based, etc.). Then you need to get your footwork basics down, you need to learn how to move around while remaining balanced. Once you can do that, then learn how to throw a decent jab, then start adding in movement, defence, and other strikes. This is something that you'll have to work out with your coach, that's what he's there for. Begin with the basics, get good at them, then add the next step. One thing at a time. Gotta learn to stand before you can walk, and walk before you can run.