ooh you do sound J, don't you! well INTJ then
do you understand the cognitive functions stuff? if not, here's a good site for reading -
Understanding the Eight Jungian Cognitive Processes / Eight Functions Attitudes. if you're an INTJ, your most-preferred function should be introverted iNtuition (Ni) and your secondary should be extraverted Thinking (Te)... if you read about those and they sound unfamiliar to you, then that's a good start for questioning your type...
the only thing that gets me is how much you sounded Ti in that first post! but then maybe that's just Ni+Te and i read it as Ti. you
do sound a little bit more... i dunno, polished or something... than the average INTP