If you two didn't have the MBTI test results, would you still be worried? If not, it might be that the insecurities have come from reading too much into type dynamics. If the fears come from lack of romantic/loving/passionate feelings in general, then you might wanna keep an eye on that. As long as you both feel happy with one another, and there's a romantic connection, don't worry.
I don't know any ENFJs so I have nothing to add there, but if it helps, I am currently in a very happy INFP/INFP relationship of 7 years, and it might be that, like we have, you find things about your partner that are wonderful, but are not seemingly present in your own personality...just because you are the same type, it does not at all mean you have to turn out to be that similar after getting to know each other more intimately.
Good luck and kind regards.
FalseHeartDothKnow