One of the least recognised qualities that effective language learners need to develop if they are to ever to get to the more advanced levels is trust. I am here talking about learning to trust ourselves, our perceptions and our abilities. Without developing this, I am afraid that continued development will just not happen.
Trust is not something you can turn on or off at will. If we don't trust our perceptions, etc there are reasons for that. One way of checking whether you are one of these people is to answer the following questions truthfully:
If you answered yes for either of these questions, there is a good likelihood that your perceptions are not guiding you. That is a recipe for very slow progress, one that will come to a premature end.
For such people, my suggestion would be to work just as hard on learning to trust yourself as you are learning English. I say this because I have seen people like this have difficulty bringing what they learn into their speech.