This is going to sound like a complete non-answer, but it's actually more useful than it sounds. It means that the test thinks you use Ni the most, then Ne and Ti, and then Fi. That's all there is to it.
More than likely the test was either wrong or you misinterpreted some of the questions. If this was a free test on the internet, I'd bet it's the former.
Shadow personality type for ENTP is INTJ which is what ENTPs most commonly switch to in times of stress. So if there have been events in your life that pressured you to use your so-called shadow functions for prolonged period of time, then you have also developed functions that INTJs use - Ni Te Fi Se. They will of course be of lower ranking order than your natural type functions. Even though some sources claim that your shadow personality type is complete inverse of your functional identity and order, other sources claim that the mind strives to keep the same functional order, as it does correspond to the most developed regions of your brain. By my personal experiences I support this later opinion - there is just no way that I flip into the ESTP mindset, having inferior function become dominant is just a huge change, but I have felt as an ENFP plenty of times - and in fact I have seen multiple reports by the ENFPs of the same, that they sometimes can approximate the INFJ mindset.