Personalities are very much fluid, and often can manifest themselves in unexpected times and places. I act and think mostly like an ISTP, but sometimes I find myself expressing more intuition and judging attributes. Your personality type is (in my opinion) influenced primarily by the environment (what you are exposed to, how you are raised) and can become cemented at a very early age. It took me until three to learn how to talk, and I think that may have put me a step behind everybody else in early life, making me more introverted because I had to rely more on my own thoughts. But unique situations and shocks to the brain that regulates your personality can change it in a heartbeat. Whether or not you are a dominant sensor or intuitive is irrelevant, what really matters is how it relates to your everyday life. Just getting to know yourself is what really matters.