Try doing this. This, and similar excersises, severely helped me change my own perceptions and thought patterns that caused issues within myself. Thoughts, negative or positive, literally form chains and link together. One thought triggers another, forming chain reactions. After some practice it becomes fairly easy to feel and see it. You might know this for a fact already, since you described “thinking too much”, so you’ll understand what it feels like when thoughts form chains.
The essence of the excersise, is figuring out what it is that you truly believe within yourself, and restructuring it in whatever way you want. Hope this helps.