How to stop overthinking everything?
Overthinking can be so overwhelming as it consumes so much time - re-thinking the same thought again and again, analyzing the thought until all sense of proportion of what actually happened may have disappeared. It sounds like when you are beginning the spiral of overthinking, other thoughts from the past of embarrassing moments begin to creep in, which sounds like it is making you feel really negatively about yourself and keeps you in that spiral of unhelpful thinking patterns.
There are helpful and unhelpful ways to look at a situation. Overthinking small situations in a way that only focuses on the negatives and then leads to thoughts of other past events that were embarrassing, sounds very unhelpful to your well-being and self-esteem. It could be that you are applying what we call "cognitive distortions" - for example, filtering out all the positive aspects of a situation and focusing purely on the negative.
Most irrational thoughts can be challenged, once you are aware of them. In therapy, we can do this by using a technique called Cognitive Behavioral Therapy (CBT). CBT works by looking at our underlying thoughts which will in turn inform how we feel about ourselves and then how we react to the world around us (our behavior). By looking at thoughts in a more objective way and reflecting on them, we can add logical evidence to try to make the thoughts more realistic.
I like to work in a holistic way - looking at the whole person - past experiences etc. rather than just what is going on in the present. So, I would suggest working in a way that combines CBT exercises with a person-centered, Humanistic approach to therapy also. The Humanistic approach in counseling believes that we are all capable of growing to be the best version of ourselves and also that we inherently understand what is best for ourselves. Problems arise from our experiences in life and also sometimes from the influence of others around us. With our understanding of what is best diminished by these, a sense of uncertainty and anxiety can creep in.
Through the counseling environment - a safe space where there is no judgement, you would be able to express your experiences in life and also your role within them. When there is no judgement, you are more likely to make honest reflections, which in turn leads to growth as a person and you are then able to make positive changes in your life.