Self awareness

There are a couple of questions I wonder about when it comes to consciousness:

Why did it happen?

How did it happen?

These questions are intertwined to some extent. I always thought that after various senses emerged, pain, which is a reinforcing impetus to avoid damage would have emerged next from an automatic reaction to those senses.

Caring about pain would be an important step in the progression from sensing the environment to becoming aware of ones place in the environment.