It's good to see you back, Economica. Have you been well?
The odd thing about it is that only some members of each type elicit this from me... some of the more balanced ones don't create this reaction or tension in me. ENFJ's and INFP's seem a bit more likely to do so, but not always (so I especially understand your response to an INFP being this way).
And you say that it's uncharacteristic for you? Why is it you don't you do this normally?
Don't worry, I'm sure we can come up with guesses and rumors that are far worse than your actual reason.(I should mention that I told him early on that I was not available. He still wanted to talk, and I wanted to talk to him for a reason I will not divulge here. )
Anyway, I've noticed that the responses from INFP's on here have varied a bit... some of them appreciate F qualities more like the person you interacted with, but others seem to appreciate the different balance introduced by a T. I suppose that's not too surprising, as INFP's often try harder than most people to be individual/personal.