Do next? You have not even scratched the surface of what you have studied. you have not developed the technique, timing, or understanding of the basics yet. A black belt in the U.S.A means a high level of skill, knowledge, ...etc. However it is only the beginning. In the orient black belts are seen as very basic beginners that may actually stick around long enough to learn something useful.
As a serious martial artist for over 42 years I know this to be true of any martial art. If you instructor is really knowledgeable, stick with him. If not then go somewhere else.
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