I could be wrong, but it seems as if you are allowing the way you feel to determine what you believe is true about yourself (i.e., that you're not creative; that you're boring, slow, and lack talent).
Have you ever asked yourself if these things must be true simply because you feel they are? The first key to discovering and accepting your own self-worth is to not allow your feelings (or related negative thoughts) to govern your beliefs about who you are. Easier said than done, I know... trust me, everyone deals with a lack of self-worth and self-respect at some point in their lives, some to a greater degree and intensity than others; however, you CAN find and develop self-respect and realize your own unique value with some help and persistence.
What books have you read? And how long would you say you have been involved/ engaged in conscious personal growth/ self-improvement?