For example, I know that I am strong enough to pick up a feather, but that I am unable to lift up a car.
I'm unsure if this is self-awareness, because it does not cover the conscious knowledge of one's feelings. Any comments?
I think knowing self is a key to many successes. You can have abilities in curriculum vitae, or in a computer game, or whenever you get known something, you achieve this ability.
You can have a path on which you plan your abilities, eg. learning plan. Then as motivation you have achieved an ability, like in this service you are achieving badges.
Ability is somehow benefiting from hard work or learning, because having ability make you at least satisfied.
There are at least two kinds of abilities:
If I read a book and talk too much about it, I forget sometimes about that book. But when I learn to ride a bicycle, I cannot forget this ability.