I took about a dozen of your longer posts and tried them in uClassify (
http://www.uclassify.com/browse). By analysis of your writing style, it says you're xSFJ. I think N is still a good possibility though since it doesn't always get that one right. xxFJ at least seems pretty likely.
Looking at the cognitive functions of FJ types, the one most similar to INTP, and therefore most likely to be mistyped as it, is ISFJ, with Si, Fe, Ti, and Ne. I think this is about as good a guess as I can come up with based solely on your writing style. To make a more accurate typing, I would have to see some actual descriptions of you as well as cognitive function test results. But for now, I'll go with ISFJ.