Worrying in itself is not a bad thing. It shows you care. When it gets to that constant and obsessive point, though, it inhibits success. You become paralyzed by fear of making a mistake, causing you to not act. Overthinking is a self-destructive behavior, taking a serious toll on both your mental and physical health. You will develop anxiety, which not only causes emotional suffering, but over time will affect your heart, digestive, and nervous system, as well as many other systems in the body. The first step to fixing a problem is understanding exactly what is going on. Overthinking is a matter of thoughts becoming stuck on a loop. Think of how a drain can get clogged. If you left the water running with it this way, pretty soon you'd have an overflowing bathtub. When you obsess over a frightening thought, for example "What if everyone secretly hates me?", not only will this take up all of your time, but it will seem to come true right before your eyes. Suddenly, everyone is giving you disapproving looks and talking to you with a short tone. Let me explain what actually happened. You were looking to see something so your mind created that reality. You are interpreting everyone's looks and words in a way that suits the fear. This is how people develop psychosomatic symptoms of a serious illness. The mind is an extremely powerful thing- learn to use this fact for your betterment instead of your detriment. Thought patterns can be created and withered. Any time you've learned worked for someone who wanted you to do things differently from your previous employer, you retrained your brain. Think about when you had to learn your multiplication tables. You thought you'd never get it down, and then after enough practice you could recite all of them from memory alone. You will have to repeat thoughts that challenge the anxiety hundreds, even thousands of times, because this is how often the cycle of worry has gone on in your mind. You have to put yourself into a place of power over your thoughts. It will also take a variety of exercises and coping mechanisms, such as yoga, meditation, and mindfulness. Don't panic if you don't know much about these. I'll tell you all about it. You are not at the mercy of your thoughts. They do not exist in the real world, or anywhere else other than your mind. They only become real if you create an intention and then follow through with action. This means your fears cannot harm you, only make you uncomfortable. Say you have a concern about your health (assuming is unfounded). Your brain might be sending you messages that you are going to get sick and die, and this might cause you feelings of intense fear, which makes the event seem imminent. When this feeling takes over, stop and step back for a moment. Look at what is actually happening around you. Your mind is playing tricks on you. No matter how scary your thoughts are on the inside, come back to reality.