Difficult to put out. I mean special snowflakism is all I see as someone just really keeps talking about the label, or a created self-image (maybe enneatype 3 relation?) for example:
"I am an INFJ. <insert indirect way of saying you're psychic>
Is this an INFJ thing? I don't know this or that is but I probably know definitely this is INFJ.
<insert indirect saying that you are needed and everybody else is stupid>"
I think that is heavy snow-flake syndrome right there. Proclaiming the rarest type isn't the only example of it however haha.
If you claim to be an INXJ, keep reading and accept the possibility you may be any of the other 14 types while understanding individual functions (especially Ni since that is a dominant feature to know about INXJ, understand the inferior function (as inferior intuition may be a cause and think about the qualities of who may be your ideal person, I believe inferior aspirations may be wanted in that ideal person), ask others how you respond to the outer world, take the socionics test and see what comes up, see how function pairs work, and understand what constitutes a judging dominant personality vs a perceiving dominant personality (as well the introversion to extroversion scales).
I wouldn't think you need (as in a must) to get a professional to type you if you thirst for the truth badly.