Why would one look down on himself or herself? We measure our qualities through the eyes of others. We so much rely on others for our gratification, that a negative statement about our person from someone may spoil our mood and destroy our motivations. When we aren't aware of this great power we give to others over our lives, we tend to want to please them at the expense of doing what is right and pleasing to us.
Self esteem is being happy with ones own characters and abilities. Every human being have their own abilities and disabilties. When one declares his/her disabilities as an excuse of not being able to do something, the mind picks this as a reference and reminds one of it everytime one attempts any task similar to the one it made the reference from.
What happens when we do something and people commend us and tell us they like how we did it and what we did. We tend to want to continue and we feel happy doing what we recieved commendation for. The mind records the feeling of joy for the task and uses that as a reference everytime the task is thought of, thus a happy feeling is felt when thinking about or planning for the task.
Dont use my disabilties as an excuse, dont rely on others for commendation, what more? Be yourself, remind yourself of past glories,learn to be better in the things you are good in, be a fan of yourself and think positive of yourself.