i'm so sick of posting this:
people are BORN an mbti type.. that's why parents often think they can spot their childs personality from when they were babies. stress and different factors may make you "become" another type- at least it will seem like it, and this is especially true of NFs who are eager to find themselves and to learn from mistakes, but essentially you will always be the type you were born with.
an anxiety suffering reculsive ENFP is not then an INFP, an NF who makes mistakes in life and decides logic is preferable is not then an NT. they will simply be stressed versions of their type and will never truly be anything like the type they claim to have "changed into/from".