Is it odd for a personality type to change over a short period of time?

Since high school, I’ve taken Myers-Briggs personality tests every so often. I was always evaluated as an INTJ – Introverted, iNtuitive, Thinking, and Judging. I took the test last week and found that I’m an ENTP (now Extroverted and Perceiving).

Is is odd that my personality has changed so much over a few years? How is this possible? Has anyone else had this experience?