I think you're trying to say, "I don't deserve this!" Meaning that something bad has happened to you that you don't deserve. To say, "I'm not worth this" means that you have very little value, which is a different meaning from what I think you're trying to say.

If someone accuses you of something you have not done, but won't listen to your explanation you can say, "I don't deserve this! " [I don't deserve to be falsely accused]