Well, I don't think it is OCD. That disorder deals with intrusive thoughts that cause you to do certain behaviors. You just seem to keep thinking about things that are keeping you down. I'm very sorry for your troubles...

I also have a low self esteem sometimes. People say I'm pretty, but I rarely believe them, because my depression makes me feel worthless. Though, I've been trying new things to try to feel better. Such as, If Im feeling bad for myself, I will take a moment to let myself feel the pity. I will let the emotions go for a bit, and maybe even cry. After I let out some pain, i decide that is enough pity for the day. I move on, and try to keep going. Sometimes it is hard to do this. Though, accepting your emotions and letting it out is a good way of getting through the rest of the day. Crying isn't just for children you know. I hope you find a way to get through this. I recommend finding a therapist to try to sort these things out.