Self-knowledge and self-esteem are tightly linked. You've obviously already drawn some conclusions about yourself: "I'm like that, I can't help it", "I'm terrible", "people don't like me" or "I annoy my friends", but these opinions do nothing but severely undermine your self-esteem.
Taking the time to discover yourself and being kind to yourself will help you make peace with who you are deep down inside. Once you have identified what you like, what you don't like or what is good or bad for you, things will be so much easier.
'We must fall in love with ourselves. I don’t like myself. I’m crazy about myself.'
- Mae West