The same person is not going to give you three different answers within span of minutes. Especially when nothing fundamentally has changed. People might or might not update their views depending on their biases.

I'm pretty sure the personality tests are created specifically for the reason that a single person can have fundamentally (or conflicting) beliefs about himself in a matter of minutes. You can say "I am honest person" and the next minute you can say "I never lie" - and both cannot be true for an average person.