A big part of the time you've spent learning is likely on just a few fundamentals. Without that first 10% getting drilled into you, the other 90% will be worthless. There is no shortcut. Time on the bag will allow you to feel how some of those fundamentals work and the conditioning it provides is needed to prepare you for more intensive training later. Many people train just with conditioning as their main goal, but if you wish to apply this to combat, perhaps that gym is not the best place for you. I train 4 hours/wk and I'm 73. Give it another 5 months and evaluate if you're getting what you want. If not, move on. Regardless, the time you are spending now is not wasted.