Hehe, that was actually a rhetorical question... But I do wonder. Maddening.
The human mind is incredibly adaptive. It is very possible that you've developed situational modes. For example, I'm an INFJ, but I've learned to lean on my Ne and Se in social situations, and before that I'd also learned how to lean on my Fi and Ne when doing artwork. It doesn't change my type, but it does change how my type functions in those situations.
When I am working on art, I start with Ni focusing on finding the solution to the problem of making the image. At this point, I only have an idea of what I want it to be, and don't know how to make it happen. This is where Ne comes in, giving me hints of possibilities and directions to take the work. The more I focus on it, the more focus on Ti, the more I let go of how I feel it should be (Fe), and center upon how I understand the artistic process to work (Ti) by slowly sketching it in. I lean into my Fi to enhance my right brained capacities for artistic subtlety to begin to focus on the details, and finally to Se where I pull back and make sure the overall image is pleasing to me. My mind still starts at Ni, moves to Fe, then Ti, then Se, but in the process swings past the other functions which support the ones in front of them.
In social situations, it is much the same, just focusing differently. I start with Ni, an impression of what is going on with whom and why. I then react to this impression by deciding how I feel these things
should be reacted to, but at this point my Fe often feels that humor is important which causes my Ti to lean on my Ne to come up with some funny. Slowly as the socializing opens me up, I come down to my Se more and more, causing me to lean more and more into it. Before long, I'm finding a balance between my Ni and Fe with my Ne and Se. Even though I'm using my Ne and Se very strongly, I still start at Ni and Fe, and am using my Ne and Se to support them.
What makes personality type is which functions you use to support which functions. Everyone is going to use all of their functions, especially with respect to situations and functions that are condusive to their use. The distinction is in how your functions support each other. All of my functions support my Ni. My Fe supports my Ni. My Ti supports my Fe most of the time, but sometimes it supports my Ni directly when my Fe has no opinion on the matter (other than I should be doing what I am doing). And so on and so forth.
If you are an INFP, all of your functions support your Fi - how you feel inside, your sense of good and bad, your conscience. If you are an INFP, then your Ne will be a common supporter of your Fi, constantly coming up with quick possibilities for how you feel, justifying what you believe is good or bad, and making sure you are being true to your conscience. Any other functions will support those two key elements in a pattern similar to the INFJ examples I gave.