We all have an image of ourselves, perhaps several. For example, we may have one image of ourselves for how we are at work, and another for our life as a family person, choir member or gardening enthusiast. These things are not fixed, neither are they an accurate reflection of how others see us. Our self-image is also likely to be pretty inaccurate, given how most of us can exaggerate our qualities, good or bad, depending on how we feel at a given moment.
It doesn’t really matter what you think of yourself because self-image is a private thing. If you fail to live up to what you aspire to be, at least you are headed in the right direction. If your self-image grossly underestimates you and makes you feel bad it can be troubling, but it’s still only a matter for yourself (unless we become a risk to ourselves or others).
It might help to think about self-image as what we do in a given situation. If you act politely you are polite, ditto with respectful behaviour, cruelty, enthusiasm, punctuality… the list is limitless. In short, how we act is what we are, in that moment.
Fortunately, self-image is like a hall of mirrors, we can protect ourselves with distortions. Unfortunately, as with low-self-esteem for example, those distortions are lies that harm us. At times like that, it can be helpful to remember that how you act is what you are, at any given moment.