I think toooo much..please help?

There's no easy way to stop the mind from tormenting itself, when if feels like it. It's a good thing that you realize, that much of what's making you depressed and paranoid is mostly your own insecurities. The next time you find yourself getting depressed over nothing just stop yourself, force your mind to think about something else, if then suddenly you find yourself thinking about the thing that makes you feel guilty and hence depressed, then try looking at it from an "outsiders" point of view. In other words, how would you judge someone who did whatever it is that you did? If you don't think it would make them bad, if you wouldn't stop being their friend, if you found out what they did, then why should you be so hard on yourself. Also remember, that the worse people in the world are usually the ones who never concern themselves with whether or not they're a bad person. :)