I hate that I hate myself

I often have thoughts of, "I hate everything" or "I hate myself," knowing that what I really mean is "I hate certain aspects of myself," or "I am upset that I did that." What's crazy is that I hate that I hate these things. I do not hate myself in general, as a whole, but there are things about me and situations which trigger these thoughts.
I recently may have made a mistake at work, and I do not look forward to working with my manager tomorrow. She's nice, and it's not a big deal--I may not have even really done anything wrong--I threw something away that was considered damaged because of packaging, but maybe it could have been sold for a lower price. I processed it in the computer, so the inventory is correct, but questioned my actions afterward.
Whenever I make a mistake, or have any reason to second-guess myself, I have these repetitive negative thoughts. When things are going well, I do not. The fact that I can identify what it is that bothers me seems like a good sign, but I feel like I can't stop having the bad feelings.

Whenever you have those thoughts, try to change the inner dialogue to "I dislike these aspects of myself", and work on improving them, or at least accepting them (well, you should accept them first in order to improve on them).